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diff --git a/manuals/bc/EN.1 b/manuals/bc/EN.1 index d7f967d96cd5..d11c6f7742a1 100644 --- a/manuals/bc/EN.1 +++ b/manuals/bc/EN.1 @@ -25,18 +25,20 @@ .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" -.TH "BC" "1" "July 2020" "Gavin D. Howard" "General Commands Manual" +.TH "BC" "1" "October 2020" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP -bc \- arbitrary\-precision arithmetic language and calculator +bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP -\f[B]bc\f[] [\f[B]\-ghilPqsvVw\f[]] [\f[B]\-\-global\-stacks\f[]] -[\f[B]\-\-help\f[]] [\f[B]\-\-interactive\f[]] [\f[B]\-\-mathlib\f[]] -[\f[B]\-\-no\-prompt\f[]] [\f[B]\-\-quiet\f[]] [\f[B]\-\-standard\f[]] -[\f[B]\-\-warn\f[]] [\f[B]\-\-version\f[]] [\f[B]\-e\f[] \f[I]expr\f[]] -[\f[B]\-\-expression\f[]=\f[I]expr\f[]...] [\f[B]\-f\f[] -\f[I]file\f[]...] [\f[B]\-file\f[]=\f[I]file\f[]...] [\f[I]file\f[]...] +\f[B]bc\f[R] [\f[B]-ghilPqsvVw\f[R]] [\f[B]\[en]global-stacks\f[R]] +[\f[B]\[en]help\f[R]] [\f[B]\[en]interactive\f[R]] +[\f[B]\[en]mathlib\f[R]] [\f[B]\[en]no-prompt\f[R]] +[\f[B]\[en]quiet\f[R]] [\f[B]\[en]standard\f[R]] [\f[B]\[en]warn\f[R]] +[\f[B]\[en]version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] +[\f[B]\[en]expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] +\f[I]file\f[R]\&...] [\f[B]-file\f[R]=\f[I]file\f[R]\&...] +[\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in @@ -44,147 +46,145 @@ bc(1) is an interactive processor for a language first standardized in (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is -somewhat C\-like, but there are differences. +somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on -the command line and executes them before reading from \f[B]stdin\f[]. +the command line and executes them before reading from \f[B]stdin\f[R]. .PP -This bc(1) is a drop\-in replacement for \f[I]any\f[] bc(1), including +This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). .SH OPTIONS .PP The following are the options that bc(1) accepts. .PP -\f[B]\-g\f[], \f[B]\-\-global\-stacks\f[] +\f[B]-g\f[R], \f[B]\[en]global-stacks\f[R] .IP .nf \f[C] -Turns\ the\ globals\ **ibase**,\ **obase**,\ and\ **scale**\ into\ stacks. +Turns the globals **ibase**, **obase**, and **scale** into stacks. -This\ has\ the\ effect\ that\ a\ copy\ of\ the\ current\ value\ of\ all\ three\ are\ pushed -onto\ a\ stack\ for\ every\ function\ call,\ as\ well\ as\ popped\ when\ every\ function -returns.\ This\ means\ that\ functions\ can\ assign\ to\ any\ and\ all\ of\ those -globals\ without\ worrying\ that\ the\ change\ will\ affect\ other\ functions. -Thus,\ a\ hypothetical\ function\ named\ **output(x,b)**\ that\ simply\ printed -**x**\ in\ base\ **b**\ could\ be\ written\ like\ this: +This has the effect that a copy of the current value of all three are pushed +onto a stack for every function call, as well as popped when every function +returns. This means that functions can assign to any and all of those +globals without worrying that the change will affect other functions. +Thus, a hypothetical function named **output(x,b)** that simply printed +**x** in base **b** could be written like this: -\ \ \ \ define\ void\ output(x,\ b)\ { -\ \ \ \ \ \ \ \ obase=b -\ \ \ \ \ \ \ \ x -\ \ \ \ } + define void output(x, b) { + obase=b + x + } -instead\ of\ like\ this: +instead of like this: -\ \ \ \ define\ void\ output(x,\ b)\ { -\ \ \ \ \ \ \ \ auto\ c -\ \ \ \ \ \ \ \ c=obase -\ \ \ \ \ \ \ \ obase=b -\ \ \ \ \ \ \ \ x -\ \ \ \ \ \ \ \ obase=c -\ \ \ \ } + define void output(x, b) { + auto c + c=obase + obase=b + x + obase=c + } -This\ makes\ writing\ functions\ much\ easier. +This makes writing functions much easier. -However,\ since\ using\ this\ flag\ means\ that\ functions\ cannot\ set\ **ibase**, -**obase**,\ or\ **scale**\ globally,\ functions\ that\ are\ made\ to\ do\ so\ cannot -work\ anymore.\ There\ are\ two\ possible\ use\ cases\ for\ that,\ and\ each\ has\ a +However, since using this flag means that functions cannot set **ibase**, +**obase**, or **scale** globally, functions that are made to do so cannot +work anymore. There are two possible use cases for that, and each has a solution. -First,\ if\ a\ function\ is\ called\ on\ startup\ to\ turn\ bc(1)\ into\ a\ number -converter,\ it\ is\ possible\ to\ replace\ that\ capability\ with\ various\ shell -aliases.\ Examples: +First, if a function is called on startup to turn bc(1) into a number +converter, it is possible to replace that capability with various shell +aliases. Examples: -\ \ \ \ alias\ d2o="bc\ \-e\ ibase=A\ \-e\ obase=8" -\ \ \ \ alias\ h2b="bc\ \-e\ ibase=G\ \-e\ obase=2" + alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] + alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] -Second,\ if\ the\ purpose\ of\ a\ function\ is\ to\ set\ **ibase**,\ **obase**,\ or -**scale**\ globally\ for\ any\ other\ purpose,\ it\ could\ be\ split\ into\ one\ to -three\ functions\ (based\ on\ how\ many\ globals\ it\ sets)\ and\ each\ of\ those -functions\ could\ return\ the\ desired\ value\ for\ a\ global. +Second, if the purpose of a function is to set **ibase**, **obase**, or +**scale** globally for any other purpose, it could be split into one to +three functions (based on how many globals it sets) and each of those +functions could return the desired value for a global. -If\ the\ behavior\ of\ this\ option\ is\ desired\ for\ every\ run\ of\ bc(1),\ then\ users -could\ make\ sure\ to\ define\ **BC_ENV_ARGS**\ and\ include\ this\ option\ (see\ the -**ENVIRONMENT\ VARIABLES**\ section\ for\ more\ details). +If the behavior of this option is desired for every run of bc(1), then users +could make sure to define **BC_ENV_ARGS** and include this option (see the +**ENVIRONMENT VARIABLES** section for more details). -If\ **\-s**,\ **\-w**,\ or\ any\ equivalents\ are\ used,\ this\ option\ is\ ignored. +If **-s**, **-w**, or any equivalents are used, this option is ignored. -This\ is\ a\ **non\-portable\ extension**. -\f[] +This is a **non-portable extension**. +\f[R] .fi .TP -.B \f[B]\-h\f[], \f[B]\-\-help\f[] +\f[B]-h\f[R], \f[B]\[en]help\f[R] Prints a usage message and quits. -.RS -.RE .TP -.B \f[B]\-i\f[], \f[B]\-\-interactive\f[] +\f[B]-i\f[R], \f[B]\[en]interactive\f[R] Forces interactive mode. -(See the \f[B]INTERACTIVE MODE\f[] section.) +(See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-l\f[], \f[B]\-\-mathlib\f[] -Sets \f[B]scale\f[] (see the \f[B]SYNTAX\f[] section) to \f[B]20\f[] and -loads the included math library before running any code, including any -expressions or files specified on the command line. +\f[B]-l\f[R], \f[B]\[en]mathlib\f[R] +Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] +and loads the included math library before running any code, including +any expressions or files specified on the command line. .RS .PP -To learn what is in the library, see the \f[B]LIBRARY\f[] section. +To learn what is in the library, see the \f[B]LIBRARY\f[R] section. .RE .TP -.B \f[B]\-P\f[], \f[B]\-\-no\-prompt\f[] +\f[B]-P\f[R], \f[B]\[en]no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. -See the \f[B]TTY MODE\f[] section) This is mostly for those users that +See the \f[B]TTY MODE\f[R] section) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in -\f[B]BC_ENV_ARGS\f[] (see the \f[B]ENVIRONMENT VARIABLES\f[] section). +\f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-q\f[], \f[B]\-\-quiet\f[] +\f[B]-q\f[R], \f[B]\[en]quiet\f[R] This option is for compatibility with the GNU -bc(1) (https://www.gnu.org/software/bc/); it is a no\-op. +bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the -\f[B]\-v\f[], \f[B]\-V\f[], or \f[B]\-\-version\f[] options are given. +\f[B]-v\f[R], \f[B]-V\f[R], or \f[B]\[en]version\f[R] options are given. .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-s\f[], \f[B]\-\-standard\f[] +\f[B]-s\f[R], \f[B]\[en]standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-v\f[], \f[B]\-V\f[], \f[B]\-\-version\f[] +\f[B]-v\f[R], \f[B]-V\f[R], \f[B]\[en]version\f[R] Print the version information (copyright header) and exit. .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-w\f[], \f[B]\-\-warn\f[] -Like \f[B]\-s\f[] and \f[B]\-\-standard\f[], except that warnings (and -not errors) are printed for non\-standard extensions and execution +\f[B]-w\f[R], \f[B]\[en]warn\f[R] +Like \f[B]-s\f[R] and \f[B]\[en]standard\f[R], except that warnings (and +not errors) are printed for non-standard extensions and execution continues normally. .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-e\f[] \f[I]expr\f[], \f[B]\-\-expression\f[]=\f[I]expr\f[] -Evaluates \f[I]expr\f[]. +\f[B]-e\f[R] \f[I]expr\f[R], \f[B]\[en]expression\f[R]=\f[I]expr\f[R] +Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. @@ -193,61 +193,61 @@ read in and evaluated first. .RS .PP After processing all expressions and files, bc(1) will exit, unless -\f[B]\-\f[] (\f[B]stdin\f[]) was given as an argument at least once to -\f[B]\-f\f[] or \f[B]\-\-file\f[]. -However, if any other \f[B]\-e\f[], \f[B]\-\-expression\f[], -\f[B]\-f\f[], or \f[B]\-\-file\f[] arguments are given after that, bc(1) -will give a fatal error and exit. +\f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to +\f[B]-f\f[R] or \f[B]\[en]file\f[R]. +However, if any other \f[B]-e\f[R], \f[B]\[en]expression\f[R], +\f[B]-f\f[R], or \f[B]\[en]file\f[R] arguments are given after that, +bc(1) will give a fatal error and exit. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]\-f\f[] \f[I]file\f[], \f[B]\-\-file\f[]=\f[I]file\f[] -Reads in \f[I]file\f[] and evaluates it, line by line, as though it were -read through \f[B]stdin\f[]. +\f[B]-f\f[R] \f[I]file\f[R], \f[B]\[en]file\f[R]=\f[I]file\f[R] +Reads in \f[I]file\f[R] and evaluates it, line by line, as though it +were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP After processing all expressions and files, bc(1) will exit, unless -\f[B]\-\f[] (\f[B]stdin\f[]) was given as an argument at least once to -\f[B]\-f\f[] or \f[B]\-\-file\f[]. +\f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to +\f[B]-f\f[R] or \f[B]\[en]file\f[R]. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .PP -All long options are \f[B]non\-portable extensions\f[]. +All long options are \f[B]non-portable extensions\f[R]. .SH STDOUT .PP -Any non\-error output is written to \f[B]stdout\f[]. +Any non-error output is written to \f[B]stdout\f[R]. .PP -\f[B]Note\f[]: Unlike other bc(1) implementations, this bc(1) will issue -a fatal error (see the \f[B]EXIT STATUS\f[] section) if it cannot write -to \f[B]stdout\f[], so if \f[B]stdout\f[] is closed, as in \f[B]bc ->&\-\f[], it will quit with an error. -This is done so that bc(1) can report problems when \f[B]stdout\f[] is +\f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will +issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot +write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in +\f[B]bc >&-\f[R], it will quit with an error. +This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to -redirect \f[B]stdout\f[] to \f[B]/dev/null\f[]. +redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP -Any error output is written to \f[B]stderr\f[]. +Any error output is written to \f[B]stderr\f[R]. .PP -\f[B]Note\f[]: Unlike other bc(1) implementations, this bc(1) will issue -a fatal error (see the \f[B]EXIT STATUS\f[] section) if it cannot write -to \f[B]stderr\f[], so if \f[B]stderr\f[] is closed, as in \f[B]bc -2>&\-\f[], it will quit with an error. +\f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will +issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot +write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in +\f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when -\f[B]stderr\f[] is redirected to a file. +\f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to -redirect \f[B]stderr\f[] to \f[B]/dev/null\f[]. +redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP -The syntax for bc(1) programs is mostly C\-like, with some differences. +The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) @@ -255,268 +255,270 @@ accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP -In the sections below, \f[B]E\f[] means expression, \f[B]S\f[] means -statement, and \f[B]I\f[] means identifier. +In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means +statement, and \f[B]I\f[R] means identifier. .PP -Identifiers (\f[B]I\f[]) start with a lowercase letter and can be -followed by any number (up to \f[B]BC_NAME_MAX\-1\f[]) of lowercase -letters (\f[B]a\-z\f[]), digits (\f[B]0\-9\f[]), and underscores -(\f[B]_\f[]). -The regex is \f[B][a\-z][a\-z0\-9_]*\f[]. +Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be +followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase +letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores +(\f[B]_\f[R]). +The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a -\f[B]non\-portable extension\f[]. +\f[B]non-portable extension\f[R]. .PP -\f[B]ibase\f[] is a global variable determining how to interpret +\f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. -It is the "input" base, or the number base used for interpreting input -numbers. -\f[B]ibase\f[] is initially \f[B]10\f[]. -If the \f[B]\-s\f[] (\f[B]\-\-standard\f[]) and \f[B]\-w\f[] -(\f[B]\-\-warn\f[]) flags were not given on the command line, the max -allowable value for \f[B]ibase\f[] is \f[B]36\f[]. -Otherwise, it is \f[B]16\f[]. -The min allowable value for \f[B]ibase\f[] is \f[B]2\f[]. -The max allowable value for \f[B]ibase\f[] can be queried in bc(1) -programs with the \f[B]maxibase()\f[] built\-in function. +It is the \[lq]input\[rq] base, or the number base used for interpreting +input numbers. +\f[B]ibase\f[R] is initially \f[B]10\f[R]. +If the \f[B]-s\f[R] (\f[B]\[en]standard\f[R]) and \f[B]-w\f[R] +(\f[B]\[en]warn\f[R]) flags were not given on the command line, the max +allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. +Otherwise, it is \f[B]16\f[R]. +The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. +The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) +programs with the \f[B]maxibase()\f[R] built-in function. .PP -\f[B]obase\f[] is a global variable determining how to output results. -It is the "output" base, or the number base used for outputting numbers. -\f[B]obase\f[] is initially \f[B]10\f[]. -The max allowable value for \f[B]obase\f[] is \f[B]BC_BASE_MAX\f[] and -can be queried in bc(1) programs with the \f[B]maxobase()\f[] built\-in +\f[B]obase\f[R] is a global variable determining how to output results. +It is the \[lq]output\[rq] base, or the number base used for outputting +numbers. +\f[B]obase\f[R] is initially \f[B]10\f[R]. +The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and +can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. -The min allowable value for \f[B]obase\f[] is \f[B]2\f[]. +The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP -The \f[I]scale\f[] of an expression is the number of digits in the -result of the expression right of the decimal point, and \f[B]scale\f[] +The \f[I]scale\f[R] of an expression is the number of digits in the +result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. -\f[B]scale\f[] is initially \f[B]0\f[]. -\f[B]scale\f[] cannot be negative. -The max allowable value for \f[B]scale\f[] is \f[B]BC_SCALE_MAX\f[] and -can be queried in bc(1) programs with the \f[B]maxscale()\f[] built\-in -function. +\f[B]scale\f[R] is initially \f[B]0\f[R]. +\f[B]scale\f[R] cannot be negative. +The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] +and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] +built-in function. .PP -bc(1) has both \f[I]global\f[] variables and \f[I]local\f[] variables. -All \f[I]local\f[] variables are local to the function; they are -parameters or are introduced in the \f[B]auto\f[] list of a function -(see the \f[B]FUNCTIONS\f[] section). +bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. +All \f[I]local\f[R] variables are local to the function; they are +parameters or are introduced in the \f[B]auto\f[R] list of a function +(see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the -\f[B]auto\f[] list, it is assumed to be \f[I]global\f[]. -If a parent function has a \f[I]local\f[] variable version of a variable -that a child function considers \f[I]global\f[], the value of that -\f[I]global\f[] variable in the child function is the value of the +\f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. +If a parent function has a \f[I]local\f[R] variable version of a +variable that a child function considers \f[I]global\f[R], the value of +that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual -\f[I]global\f[] variable. +\f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence -operator is an assignment operator \f[I]and\f[] the expression is +operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable -\f[B]last\f[]. -A single dot (\f[B].\f[]) may also be used as a synonym for -\f[B]last\f[]. -These are \f[B]non\-portable extensions\f[]. +\f[B]last\f[R]. +A single dot (\f[B].\f[R]) may also be used as a synonym for +\f[B]last\f[R]. +These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 -Block comments are enclosed in \f[B]/*\f[] and \f[B]*/\f[]. +Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 -Line comments go from \f[B]#\f[] until, and not including, the next +Line comments go from \f[B]#\f[R] until, and not including, the next newline. -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 -Variables: \f[B]I\f[] +Variables: \f[B]I\f[R] .IP "2." 3 -Array Elements: \f[B]I[E]\f[] +Array Elements: \f[B]I[E]\f[R] .IP "3." 3 -\f[B]ibase\f[] +\f[B]ibase\f[R] .IP "4." 3 -\f[B]obase\f[] +\f[B]obase\f[R] .IP "5." 3 -\f[B]scale\f[] +\f[B]scale\f[R] .IP "6." 3 -\f[B]last\f[] or a single dot (\f[B].\f[]) +\f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP -Number 6 is a \f[B]non\-portable extension\f[]. +Number 6 is a \f[B]non-portable extension\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. -This also applies to functions (see the \f[B]FUNCTIONS\f[] section), so +This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of -\f[B]increment\f[]/\f[B]decrement\f[] operators and as the left side of -\f[B]assignment\f[] operators (see the \f[I]Operators\f[] subsection). +\f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side +of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] +subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 -Numbers (see the \f[I]Numbers\f[] subsection below). +Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 -Array indices (\f[B]I[E]\f[]). +Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 -\f[B](E)\f[]: The value of \f[B]E\f[] (used to change precedence). +\f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 -\f[B]sqrt(E)\f[]: The square root of \f[B]E\f[]. -\f[B]E\f[] must be non\-negative. +\f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. +\f[B]E\f[R] must be non-negative. .IP " 5." 4 -\f[B]length(E)\f[]: The number of significant decimal digits in -\f[B]E\f[]. +\f[B]length(E)\f[R]: The number of significant decimal digits in +\f[B]E\f[R]. .IP " 6." 4 -\f[B]length(I[])\f[]: The number of elements in the array \f[B]I\f[]. -This is a \f[B]non\-portable extension\f[]. +\f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. +This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 -\f[B]scale(E)\f[]: The \f[I]scale\f[] of \f[B]E\f[]. +\f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 -\f[B]abs(E)\f[]: The absolute value of \f[B]E\f[]. -This is a \f[B]non\-portable extension\f[]. +\f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. +This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 -\f[B]I()\f[], \f[B]I(E)\f[], \f[B]I(E, E)\f[], and so on, where -\f[B]I\f[] is an identifier for a non\-\f[B]void\f[] function (see the -\f[I]Void Functions\f[] subsection of the \f[B]FUNCTIONS\f[] section). -The \f[B]E\f[] argument(s) may also be arrays of the form \f[B]I[]\f[], -which will automatically be turned into array references (see the -\f[I]Array References\f[] subsection of the \f[B]FUNCTIONS\f[] section) -if the corresponding parameter in the function definition is an array -reference. +\f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where +\f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the +\f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). +The \f[B]E\f[R] argument(s) may also be arrays of the form +\f[B]I[]\f[R], which will automatically be turned into array references +(see the \f[I]Array References\f[R] subsection of the +\f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the +function definition is an array reference. .IP "10." 4 -\f[B]read()\f[]: Reads a line from \f[B]stdin\f[] and uses that as an +\f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. -The result of that expression is the result of the \f[B]read()\f[] +The result of that expression is the result of the \f[B]read()\f[R] operand. -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .IP "11." 4 -\f[B]maxibase()\f[]: The max allowable \f[B]ibase\f[]. -This is a \f[B]non\-portable extension\f[]. +\f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. +This is a \f[B]non-portable extension\f[R]. .IP "12." 4 -\f[B]maxobase()\f[]: The max allowable \f[B]obase\f[]. -This is a \f[B]non\-portable extension\f[]. +\f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. +This is a \f[B]non-portable extension\f[R]. .IP "13." 4 -\f[B]maxscale()\f[]: The max allowable \f[B]scale\f[]. -This is a \f[B]non\-portable extension\f[]. +\f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. +This is a \f[B]non-portable extension\f[R]. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most -\f[B]1\f[] period for a radix. -Numbers can have up to \f[B]BC_NUM_MAX\f[] digits. -Uppercase letters are equal to \f[B]9\f[] + their position in the -alphabet (i.e., \f[B]A\f[] equals \f[B]10\f[], or \f[B]9+1\f[]). +\f[B]1\f[R] period for a radix. +Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. +Uppercase letters are equal to \f[B]9\f[R] + their position in the +alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of -\f[B]ibase\f[], they are set to the value of the highest valid digit in -\f[B]ibase\f[]. +\f[B]ibase\f[R], they are set to the value of the highest valid digit in +\f[B]ibase\f[R]. .PP -Single\-character numbers (i.e., \f[B]A\f[] alone) take the value that +Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of -\f[B]ibase\f[]. -This means that \f[B]A\f[] alone always equals decimal \f[B]10\f[] and -\f[B]Z\f[] alone always equals decimal \f[B]35\f[]. +\f[B]ibase\f[R]. +This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and +\f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP -.B \f[B]++\f[] \f[B]\-\-\f[] +\f[B]++\f[R] \f[B]\[en]\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP -Description: \f[B]increment\f[], \f[B]decrement\f[] +Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP -.B \f[B]\-\f[] \f[B]!\f[] +\f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP -Description: \f[B]negation\f[], \f[B]boolean not\f[] +Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP -.B \f[B]^\f[] +\f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP -Description: \f[B]power\f[] +Description: \f[B]power\f[R] .RE .TP -.B \f[B]*\f[] \f[B]/\f[] \f[B]%\f[] +\f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP -Description: \f[B]multiply\f[], \f[B]divide\f[], \f[B]modulus\f[] +Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP -.B \f[B]+\f[] \f[B]\-\f[] +\f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP -Description: \f[B]add\f[], \f[B]subtract\f[] +Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP -.B \f[B]=\f[] \f[B]+=\f[] \f[B]\-=\f[] \f[B]*=\f[] \f[B]/=\f[] \f[B]%=\f[] \f[B]^=\f[] +\f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] Type: Binary .RS .PP Associativity: Right .PP -Description: \f[B]assignment\f[] +Description: \f[B]assignment\f[R] .RE .TP -.B \f[B]==\f[] \f[B]<=\f[] \f[B]>=\f[] \f[B]!=\f[] \f[B]<\f[] \f[B]>\f[] +\f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP -Description: \f[B]relational\f[] +Description: \f[B]relational\f[R] .RE .TP -.B \f[B]&&\f[] +\f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP -Description: \f[B]boolean and\f[] +Description: \f[B]boolean and\f[R] .RE .TP -.B \f[B]||\f[] +\f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP -Description: \f[B]boolean or\f[] +Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP -.B \f[B]++\f[] \f[B]\-\-\f[] -The prefix and postfix \f[B]increment\f[] and \f[B]decrement\f[] +\f[B]++\f[R] \f[B]\[en]\f[R] +The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. -They require a named expression (see the \f[I]Named Expressions\f[] +They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP @@ -524,205 +526,199 @@ The prefix versions of these operators are more efficient; use them where possible. .RE .TP -.B \f[B]\-\f[] -The \f[B]negation\f[] operator returns \f[B]0\f[] if a user attempts to -negate any expression with the value \f[B]0\f[]. +\f[B]-\f[R] +The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts +to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. -.RS -.RE .TP -.B \f[B]!\f[] -The \f[B]boolean not\f[] operator returns \f[B]1\f[] if the expression -is \f[B]0\f[], or \f[B]0\f[] otherwise. +\f[B]!\f[R] +The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression +is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]^\f[] -The \f[B]power\f[] operator (not the \f[B]exclusive or\f[] operator, as -it would be in C) takes two expressions and raises the first to the +\f[B]\[ha]\f[R] +The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, +as it would be in C) takes two expressions and raises the first to the power of the value of the second. +The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP -The second expression must be an integer (no \f[I]scale\f[]), and if it -is negative, the first value must be non\-zero. +The second expression must be an integer (no \f[I]scale\f[R]), and if it +is negative, the first value must be non-zero. .RE .TP -.B \f[B]*\f[] -The \f[B]multiply\f[] operator takes two expressions, multiplies them, +\f[B]*\f[R] +The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. -If \f[B]a\f[] is the \f[I]scale\f[] of the first expression and -\f[B]b\f[] is the \f[I]scale\f[] of the second expression, the -\f[I]scale\f[] of the result is equal to -\f[B]min(a+b,max(scale,a,b))\f[] where \f[B]min()\f[] and \f[B]max()\f[] -return the obvious values. -.RS -.RE +If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and +\f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the +\f[I]scale\f[R] of the result is equal to +\f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and +\f[B]max()\f[R] return the obvious values. .TP -.B \f[B]/\f[] -The \f[B]divide\f[] operator takes two expressions, divides them, and +\f[B]/\f[R] +The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. -The \f[I]scale\f[] of the result shall be the value of \f[B]scale\f[]. +The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP -The second expression must be non\-zero. +The second expression must be non-zero. .RE .TP -.B \f[B]%\f[] -The \f[B]modulus\f[] operator takes two expressions, \f[B]a\f[] and -\f[B]b\f[], and evaluates them by 1) Computing \f[B]a/b\f[] to current -\f[B]scale\f[] and 2) Using the result of step 1 to calculate -\f[B]a\-(a/b)*b\f[] to \f[I]scale\f[] -\f[B]max(scale+scale(b),scale(a))\f[]. +\f[B]%\f[R] +The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and +\f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current +\f[B]scale\f[R] and 2) Using the result of step 1 to calculate +\f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] +\f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP -The second expression must be non\-zero. +The second expression must be non-zero. .RE .TP -.B \f[B]+\f[] -The \f[B]add\f[] operator takes two expressions, \f[B]a\f[] and -\f[B]b\f[], and returns the sum, with a \f[I]scale\f[] equal to the max -of the \f[I]scale\f[]s of \f[B]a\f[] and \f[B]b\f[]. -.RS -.RE +\f[B]+\f[R] +The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and +\f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the +max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP -.B \f[B]\-\f[] -The \f[B]subtract\f[] operator takes two expressions, \f[B]a\f[] and -\f[B]b\f[], and returns the difference, with a \f[I]scale\f[] equal to -the max of the \f[I]scale\f[]s of \f[B]a\f[] and \f[B]b\f[]. -.RS -.RE +\f[B]-\f[R] +The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and +\f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to +the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP -.B \f[B]=\f[] \f[B]+=\f[] \f[B]\-=\f[] \f[B]*=\f[] \f[B]/=\f[] \f[B]%=\f[] \f[B]^=\f[] -The \f[B]assignment\f[] operators take two expressions, \f[B]a\f[] and -\f[B]b\f[] where \f[B]a\f[] is a named expression (see the \f[I]Named -Expressions\f[] subsection). +\f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] +The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and +\f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named +Expressions\f[R] subsection). .RS .PP -For \f[B]=\f[], \f[B]b\f[] is copied and the result is assigned to -\f[B]a\f[]. -For all others, \f[B]a\f[] and \f[B]b\f[] are applied as operands to the -corresponding arithmetic operator and the result is assigned to -\f[B]a\f[]. +For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to +\f[B]a\f[R]. +For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to +the corresponding arithmetic operator and the result is assigned to +\f[B]a\f[R]. .RE .TP -.B \f[B]==\f[] \f[B]<=\f[] \f[B]>=\f[] \f[B]!=\f[] \f[B]<\f[] \f[B]>\f[] -The \f[B]relational\f[] operators compare two expressions, \f[B]a\f[] -and \f[B]b\f[], and if the relation holds, according to C language -semantics, the result is \f[B]1\f[]. -Otherwise, it is \f[B]0\f[]. +\f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] +The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] +and \f[B]b\f[R], and if the relation holds, according to C language +semantics, the result is \f[B]1\f[R]. +Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the -\f[B]assignment\f[] operators, which means that \f[B]a=b>c\f[] is -interpreted as \f[B](a=b)>c\f[]. +\f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is +interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. -This allowance is a \f[B]non\-portable extension\f[]. +This allowance is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]&&\f[] -The \f[B]boolean and\f[] operator takes two expressions and returns -\f[B]1\f[] if both expressions are non\-zero, \f[B]0\f[] otherwise. +\f[B]&&\f[R] +The \f[B]boolean and\f[R] operator takes two expressions and returns +\f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP -This is \f[I]not\f[] a short\-circuit operator. +This is \f[I]not\f[R] a short-circuit operator. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .TP -.B \f[B]||\f[] -The \f[B]boolean or\f[] operator takes two expressions and returns -\f[B]1\f[] if one of the expressions is non\-zero, \f[B]0\f[] otherwise. +\f[B]||\f[R] +The \f[B]boolean or\f[R] operator takes two expressions and returns +\f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] +otherwise. .RS .PP -This is \f[I]not\f[] a short\-circuit operator. +This is \f[I]not\f[R] a short-circuit operator. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 -\f[B]E\f[] +\f[B]E\f[R] .IP " 2." 4 -\f[B]{\f[] \f[B]S\f[] \f[B];\f[] ... -\f[B];\f[] \f[B]S\f[] \f[B]}\f[] +\f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] +\f[B]}\f[R] .IP " 3." 4 -\f[B]if\f[] \f[B](\f[] \f[B]E\f[] \f[B])\f[] \f[B]S\f[] +\f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 -\f[B]if\f[] \f[B](\f[] \f[B]E\f[] \f[B])\f[] \f[B]S\f[] \f[B]else\f[] -\f[B]S\f[] +\f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] +\f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 -\f[B]while\f[] \f[B](\f[] \f[B]E\f[] \f[B])\f[] \f[B]S\f[] +\f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 -\f[B]for\f[] \f[B](\f[] \f[B]E\f[] \f[B];\f[] \f[B]E\f[] \f[B];\f[] -\f[B]E\f[] \f[B])\f[] \f[B]S\f[] +\f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] +\f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 -\f[B]break\f[] +\f[B]break\f[R] .IP " 9." 4 -\f[B]continue\f[] +\f[B]continue\f[R] .IP "10." 4 -\f[B]quit\f[] +\f[B]quit\f[R] .IP "11." 4 -\f[B]halt\f[] +\f[B]halt\f[R] .IP "12." 4 -\f[B]limits\f[] +\f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 -\f[B]print\f[] \f[B]E\f[] \f[B],\f[] ... -\f[B],\f[] \f[B]E\f[] +\f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 -\f[B]I()\f[], \f[B]I(E)\f[], \f[B]I(E, E)\f[], and so on, where -\f[B]I\f[] is an identifier for a \f[B]void\f[] function (see the -\f[I]Void Functions\f[] subsection of the \f[B]FUNCTIONS\f[] section). -The \f[B]E\f[] argument(s) may also be arrays of the form \f[B]I[]\f[], -which will automatically be turned into array references (see the -\f[I]Array References\f[] subsection of the \f[B]FUNCTIONS\f[] section) -if the corresponding parameter in the function definition is an array -reference. +\f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where +\f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the +\f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). +The \f[B]E\f[R] argument(s) may also be arrays of the form +\f[B]I[]\f[R], which will automatically be turned into array references +(see the \f[I]Array References\f[R] subsection of the +\f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the +function definition is an array reference. .PP -Numbers 4, 9, 11, 12, 14, and 15 are \f[B]non\-portable extensions\f[]. +Numbers 4, 9, 11, 12, 14, and 15 are \f[B]non-portable extensions\f[R]. .PP -Also, as a \f[B]non\-portable extension\f[], any or all of the +Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a -constant \f[B]1\f[]. +constant \f[B]1\f[R]. .PP -The \f[B]break\f[] statement causes a loop to stop iterating and resume +The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP -The \f[B]continue\f[] statement causes a loop iteration to stop early +The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP -The \f[B]if\f[] \f[B]else\f[] statement does the same thing as in C. +The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP -The \f[B]quit\f[] statement causes bc(1) to quit, even if it is on a -branch that will not be executed (it is a compile\-time command). +The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a +branch that will not be executed (it is a compile-time command). .PP -The \f[B]halt\f[] statement causes bc(1) to quit, if it is executed. -(Unlike \f[B]quit\f[] if it is on a branch of an \f[B]if\f[] statement +The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. +(Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP -The \f[B]limits\f[] statement prints the limits that this bc(1) is +The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. -This is like the \f[B]quit\f[] statement in that it is a compile\-time +This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .SS Print Statement .PP -The "expressions" in a \f[B]print\f[] statement may also be strings. +The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be +strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown @@ -732,152 +728,152 @@ below: tab(@); l l. T{ -\f[B]\\a\f[] +\f[B]\[rs]a\f[R] T}@T{ -\f[B]\\a\f[] +\f[B]\[rs]a\f[R] T} T{ -\f[B]\\b\f[] +\f[B]\[rs]b\f[R] T}@T{ -\f[B]\\b\f[] +\f[B]\[rs]b\f[R] T} T{ -\f[B]\\\\\f[] +\f[B]\[rs]\[rs]\f[R] T}@T{ -\f[B]\\\f[] +\f[B]\[rs]\f[R] T} T{ -\f[B]\\e\f[] +\f[B]\[rs]e\f[R] T}@T{ -\f[B]\\\f[] +\f[B]\[rs]\f[R] T} T{ -\f[B]\\f\f[] +\f[B]\[rs]f\f[R] T}@T{ -\f[B]\\f\f[] +\f[B]\[rs]f\f[R] T} T{ -\f[B]\\n\f[] +\f[B]\[rs]n\f[R] T}@T{ -\f[B]\\n\f[] +\f[B]\[rs]n\f[R] T} T{ -\f[B]\\q\f[] +\f[B]\[rs]q\f[R] T}@T{ -\f[B]"\f[] +\f[B]\[dq]\f[R] T} T{ -\f[B]\\r\f[] +\f[B]\[rs]r\f[R] T}@T{ -\f[B]\\r\f[] +\f[B]\[rs]r\f[R] T} T{ -\f[B]\\t\f[] +\f[B]\[rs]t\f[R] T}@T{ -\f[B]\\t\f[] +\f[B]\[rs]t\f[R] T} .TE .PP Any other character following a backslash causes the backslash and -character to be printed as\-is. +character to be printed as-is. .PP -Any non\-string expression in a print statement shall be assigned to -\f[B]last\f[], like any other expression that is printed. +Any non-string expression in a print statement shall be assigned to +\f[B]last\f[R], like any other expression that is printed. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. -This means, for example, assuming that \f[B]i\f[] is equal to -\f[B]0\f[], in the expression +This means, for example, assuming that \f[B]i\f[R] is equal to +\f[B]0\f[R], in the expression .IP .nf \f[C] -a[i++]\ =\ i++ -\f[] +a[i++] = i++ +\f[R] .fi .PP -the first (or 0th) element of \f[B]a\f[] is set to \f[B]1\f[], and -\f[B]i\f[] is equal to \f[B]2\f[] at the end of the expression. +the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and +\f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. -Thus, assuming \f[B]i\f[] is equal to \f[B]0\f[], this means that in the -expression +Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in +the expression .IP .nf \f[C] -x(i++,\ i++) -\f[] +x(i++, i++) +\f[R] .fi .PP -the first argument passed to \f[B]x()\f[] is \f[B]0\f[], and the second -argument is \f[B]1\f[], while \f[B]i\f[] is equal to \f[B]2\f[] before -the function starts executing. +the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the +second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to +\f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] -define\ I(I,...,I){ -\ \ \ \ auto\ I,...,I -\ \ \ \ S;...;S -\ \ \ \ return(E) +define I(I,...,I){ + auto I,...,I + S;...;S + return(E) } -\f[] +\f[R] .fi .PP -Any \f[B]I\f[] in the parameter list or \f[B]auto\f[] list may be -replaced with \f[B]I[]\f[] to make a parameter or \f[B]auto\f[] var an -array, and any \f[B]I\f[] in the parameter list may be replaced with -\f[B]*I[]\f[] to make a parameter an array reference. +Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be +replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an +array, and any \f[B]I\f[R] in the parameter list may be replaced with +\f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an -asterisk in the call; they must be called with just \f[B]I[]\f[] like +asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP -As a \f[B]non\-portable extension\f[], the opening brace of a -\f[B]define\f[] statement may appear on the next line. +As a \f[B]non-portable extension\f[R], the opening brace of a +\f[B]define\f[R] statement may appear on the next line. .PP -As a \f[B]non\-portable extension\f[], the return statement may also be +As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 -\f[B]return\f[] +\f[B]return\f[R] .IP "2." 3 -\f[B]return\f[] \f[B](\f[] \f[B])\f[] +\f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 -\f[B]return\f[] \f[B]E\f[] +\f[B]return\f[R] \f[B]E\f[R] .PP -The first two, or not specifying a \f[B]return\f[] statement, is -equivalent to \f[B]return (0)\f[], unless the function is a -\f[B]void\f[] function (see the \f[I]Void Functions\f[] subsection +The first two, or not specifying a \f[B]return\f[R] statement, is +equivalent to \f[B]return (0)\f[R], unless the function is a +\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP -Functions can also be \f[B]void\f[] functions, defined as follows: +Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] -define\ void\ I(I,...,I){ -\ \ \ \ auto\ I,...,I -\ \ \ \ S;...;S -\ \ \ \ return +define void I(I,...,I){ + auto I,...,I + S;...;S + return } -\f[] +\f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP -Void functions can only use the first two \f[B]return\f[] statements +Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP -The word "void" is not treated as a keyword; it is still possible to -have variables, arrays, and functions named \f[B]void\f[]. -The word "void" is only treated specially right after the -\f[B]define\f[] keyword. +The word \[lq]void\[rq] is not treated as a keyword; it is still +possible to have variables, arrays, and functions named \f[B]void\f[R]. +The word \[lq]void\[rq] is only treated specially right after the +\f[B]define\f[R] keyword. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the @@ -886,73 +882,73 @@ form .nf \f[C] *I[] -\f[] +\f[R] .fi .PP -it is a \f[B]reference\f[]. +it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP -This is a \f[B]non\-portable extension\f[]. +This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP -All of the functions below are available when the \f[B]\-l\f[] or -\f[B]\-\-mathlib\f[] command\-line flags are given. +All of the functions below are available when the \f[B]-l\f[R] or +\f[B]\[en]mathlib\f[R] command-line flags are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP -.B \f[B]s(x)\f[] -Returns the sine of \f[B]x\f[], which is assumed to be in radians. +\f[B]s(x)\f[R] +Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .TP -.B \f[B]c(x)\f[] -Returns the cosine of \f[B]x\f[], which is assumed to be in radians. +\f[B]c(x)\f[R] +Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .TP -.B \f[B]a(x)\f[] -Returns the arctangent of \f[B]x\f[], in radians. +\f[B]a(x)\f[R] +Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .TP -.B \f[B]l(x)\f[] -Returns the natural logarithm of \f[B]x\f[]. +\f[B]l(x)\f[R] +Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .TP -.B \f[B]e(x)\f[] -Returns the mathematical constant \f[B]e\f[] raised to the power of -\f[B]x\f[]. +\f[B]e(x)\f[R] +Returns the mathematical constant \f[B]e\f[R] raised to the power of +\f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .TP -.B \f[B]j(x, n)\f[] -Returns the bessel integer order \f[B]n\f[] (truncated) of \f[B]x\f[]. +\f[B]j(x, n)\f[R] +Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental -Functions\f[] subsection below). +Functions\f[R] subsection below). .RE .SS Transcendental Functions .PP @@ -964,27 +960,27 @@ why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those -functions with the precision (\f[B]scale\f[]) set to at least 1 higher +functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. -If exact results are \f[I]absolutely\f[] required, users can double the -precision (\f[B]scale\f[]) and then truncate. +If exact results are \f[I]absolutely\f[R] required, users can double the +precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 -\f[B]s(x)\f[] +\f[B]s(x)\f[R] .IP \[bu] 2 -\f[B]c(x)\f[] +\f[B]c(x)\f[R] .IP \[bu] 2 -\f[B]a(x)\f[] +\f[B]a(x)\f[R] .IP \[bu] 2 -\f[B]l(x)\f[] +\f[B]l(x)\f[R] .IP \[bu] 2 -\f[B]e(x)\f[] +\f[B]e(x)\f[R] .IP \[bu] 2 -\f[B]j(x, n)\f[] +\f[B]j(x, n)\f[R] .SH RESET .PP -When bc(1) encounters an error or a signal that it has a non\-default +When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP @@ -997,7 +993,7 @@ Then the execution point is set so that any code waiting to execute Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error -(see the \f[B]EXIT STATUS\f[] section), it asks for more input; +(see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which @@ -1005,259 +1001,230 @@ attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP -Most bc(1) implementations use \f[B]char\f[] types to calculate the -value of \f[B]1\f[] decimal digit at a time, but that can be slow. +Most bc(1) implementations use \f[B]char\f[R] types to calculate the +value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP -It uses large integers to calculate more than \f[B]1\f[] decimal digit +It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. -If built in a environment where \f[B]BC_LONG_BIT\f[] (see the -\f[B]LIMITS\f[] section) is \f[B]64\f[], then each integer has -\f[B]9\f[] decimal digits. -If built in an environment where \f[B]BC_LONG_BIT\f[] is \f[B]32\f[] -then each integer has \f[B]4\f[] decimal digits. +If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the +\f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has +\f[B]9\f[R] decimal digits. +If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] +then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called -\f[B]BC_BASE_DIGS\f[]. +\f[B]BC_BASE_DIGS\f[R]. .PP -The actual values of \f[B]BC_LONG_BIT\f[] and \f[B]BC_BASE_DIGS\f[] can -be queried with the \f[B]limits\f[] statement. +The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] +can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. -This integer type depends on the value of \f[B]BC_LONG_BIT\f[], but is +This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP -.B \f[B]BC_LONG_BIT\f[] -The number of bits in the \f[B]long\f[] type in the environment where +\f[B]BC_LONG_BIT\f[R] +The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large -integer (see the \f[B]PERFORMANCE\f[] section). -.RS -.RE +integer (see the \f[B]PERFORMANCE\f[R] section). .TP -.B \f[B]BC_BASE_DIGS\f[] +\f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the -\f[B]PERFORMANCE\f[] section). -Depends on \f[B]BC_LONG_BIT\f[]. -.RS -.RE +\f[B]PERFORMANCE\f[R] section). +Depends on \f[B]BC_LONG_BIT\f[R]. .TP -.B \f[B]BC_BASE_POW\f[] +\f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see -\f[B]BC_BASE_DIGS\f[]) plus \f[B]1\f[]. -Depends on \f[B]BC_BASE_DIGS\f[]. -.RS -.RE +\f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. +Depends on \f[B]BC_BASE_DIGS\f[R]. .TP -.B \f[B]BC_OVERFLOW_MAX\f[] -The max number that the overflow type (see the \f[B]PERFORMANCE\f[] +\f[B]BC_OVERFLOW_MAX\f[R] +The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. -Depends on \f[B]BC_LONG_BIT\f[]. -.RS -.RE +Depends on \f[B]BC_LONG_BIT\f[R]. .TP -.B \f[B]BC_BASE_MAX\f[] +\f[B]BC_BASE_MAX\f[R] The maximum output base. -Set at \f[B]BC_BASE_POW\f[]. -.RS -.RE +Set at \f[B]BC_BASE_POW\f[R]. .TP -.B \f[B]BC_DIM_MAX\f[] +\f[B]BC_DIM_MAX\f[R] The maximum size of arrays. -Set at \f[B]SIZE_MAX\-1\f[]. -.RS -.RE +Set at \f[B]SIZE_MAX-1\f[R]. .TP -.B \f[B]BC_SCALE_MAX\f[] -The maximum \f[B]scale\f[]. -Set at \f[B]BC_OVERFLOW_MAX\-1\f[]. -.RS -.RE +\f[B]BC_SCALE_MAX\f[R] +The maximum \f[B]scale\f[R]. +Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP -.B \f[B]BC_STRING_MAX\f[] +\f[B]BC_STRING_MAX\f[R] The maximum length of strings. -Set at \f[B]BC_OVERFLOW_MAX\-1\f[]. -.RS -.RE +Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP -.B \f[B]BC_NAME_MAX\f[] +\f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. -Set at \f[B]BC_OVERFLOW_MAX\-1\f[]. -.RS -.RE +Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP -.B \f[B]BC_NUM_MAX\f[] +\f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. -Set at \f[B]BC_OVERFLOW_MAX\-1\f[]. -.RS -.RE +Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP -.B Exponent +Exponent The maximum allowable exponent (positive or negative). -Set at \f[B]BC_OVERFLOW_MAX\f[]. -.RS -.RE +Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP -.B Number of vars +Number of vars The maximum number of vars/arrays. -Set at \f[B]SIZE_MAX\-1\f[]. -.RS -.RE +Set at \f[B]SIZE_MAX-1\f[R]. .PP -The actual values can be queried with the \f[B]limits\f[] statement. +The actual values can be queried with the \f[B]limits\f[R] statement. .PP -These limits are meant to be effectively non\-existent; the limits are -so large (at least on 64\-bit machines) that there should not be any -point at which they become a problem. +These limits are meant to be effectively non-existent; the limits are so +large (at least on 64-bit machines) that there should not be any point +at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP -.B \f[B]POSIXLY_CORRECT\f[] +\f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if -the \f[B]\-s\f[] option was given. -.RS -.RE +the \f[B]-s\f[R] option was given. .TP -.B \f[B]BC_ENV_ARGS\f[] -This is another way to give command\-line arguments to bc(1). -They should be in the same format as all other command\-line arguments. +\f[B]BC_ENV_ARGS\f[R] +This is another way to give command-line arguments to bc(1). +They should be in the same format as all other command-line arguments. These are always processed first, so any files given in -\f[B]BC_ENV_ARGS\f[] will be processed before arguments and files given -on the command\-line. -This gives the user the ability to set up "standard" options and files -to be used at every invocation. +\f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given +on the command-line. +This gives the user the ability to set up \[lq]standard\[rq] options and +files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP -The code that parses \f[B]BC_ENV_ARGS\f[] will correctly handle quoted +The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. -For example, the string \f[B]"/home/gavin/some bc file.bc"\f[] will be -correctly parsed, but the string \f[B]"/home/gavin/some "bc" -file.bc"\f[] will include the backslashes. +For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] +will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some +\[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP -The quote parsing will handle either kind of quotes, \f[B]\[aq]\f[] or -\f[B]"\f[]. -Thus, if you have a file with any number of single quotes in the name, -you can use double quotes as the outside quotes, as in \f[B]"some -\[aq]bc\[aq] file.bc"\f[], and vice versa if you have a file with double -quotes. +The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or +\f[B]\[lq]\f[R]. Thus, if you have a file with any number of single +quotes in the name, you can use double quotes as the outside quotes, as +in \f[B]\[rq]some `bc' file.bc\[dq]\f[R], and vice versa if you have a +file with double quotes. However, handling a file with both kinds of quotes in -\f[B]BC_ENV_ARGS\f[] is not supported due to the complexity of the -parsing, though such files are still supported on the command\-line -where the parsing is done by the shell. +\f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the +parsing, though such files are still supported on the command-line where +the parsing is done by the shell. .RE .TP -.B \f[B]BC_LINE_LENGTH\f[] +\f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is -greater than \f[B]1\f[] and is less than \f[B]UINT16_MAX\f[] -(\f[B]2^16\-1\f[]), bc(1) will output lines to that length, including -the backslash (\f[B]\\\f[]). -The default line length is \f[B]70\f[]. -.RS -.RE +greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] +(\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, +including the backslash (\f[B]\[rs]\f[R]). +The default line length is \f[B]70\f[R]. .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP -.B \f[B]0\f[] +\f[B]0\f[R] No error. -.RS -.RE .TP -.B \f[B]1\f[] +\f[B]1\f[R] A math error occurred. -This follows standard practice of using \f[B]1\f[] for expected errors, +This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP -Math errors include divide by \f[B]0\f[], taking the square root of a +Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, and -attempting to use a non\-integer where an integer is required. +attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the -power (\f[B]^\f[]) operator and the corresponding assignment operator. +power (\f[B]\[ha]\f[R]) operator and the corresponding assignment +operator. .RE .TP -.B \f[B]2\f[] +\f[B]2\f[R] A parse error occurred. .RS .PP -Parse errors include unexpected \f[B]EOF\f[], using an invalid +Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the -\f[I]Named Expressions\f[] subsection of the \f[B]SYNTAX\f[] section), -giving an invalid \f[B]auto\f[] list, having a duplicate -\f[B]auto\f[]/function parameter, failing to find the end of a code -block, attempting to return a value from a \f[B]void\f[] function, +\f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), +giving an invalid \f[B]auto\f[R] list, having a duplicate +\f[B]auto\f[R]/function parameter, failing to find the end of a code +block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions -when the option \f[B]\-s\f[] or any equivalents were given. +when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP -.B \f[B]3\f[] +\f[B]3\f[R] A runtime error occurred. .RS .PP -Runtime errors include assigning an invalid number to \f[B]ibase\f[], -\f[B]obase\f[], or \f[B]scale\f[]; give a bad expression to a -\f[B]read()\f[] call, calling \f[B]read()\f[] inside of a -\f[B]read()\f[] call, type errors, passing the wrong number of arguments -to functions, attempting to call an undefined function, and attempting -to use a \f[B]void\f[] function call as a value in an expression. +Runtime errors include assigning an invalid number to \f[B]ibase\f[R], +\f[B]obase\f[R], or \f[B]scale\f[R]; give a bad expression to a +\f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a +\f[B]read()\f[R] call, type errors, passing the wrong number of +arguments to functions, attempting to call an undefined function, and +attempting to use a \f[B]void\f[R] function call as a value in an +expression. .RE .TP -.B \f[B]4\f[] +\f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a -directory as a file, and giving invalid command\-line options. +directory as a file, and giving invalid command-line options. .RE .PP -The exit status \f[B]4\f[] is special; when a fatal error occurs, bc(1) -always exits and returns \f[B]4\f[], no matter what mode bc(1) is in. +The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) +always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in -interactive mode (see the \f[B]INTERACTIVE MODE\f[] section), since -bc(1) resets its state (see the \f[B]RESET\f[] section) and accepts more -input when one of those errors occurs in interactive mode. +interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since +bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts +more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the -\f[B]\-i\f[] flag or \f[B]\-\-interactive\f[] option. +\f[B]-i\f[R] flag or \f[B]\[en]interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the -\f[B]\-i\f[] flag or \f[B]\-\-interactive\f[] option. +\f[B]-i\f[R] flag or \f[B]\[en]interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), -bc(1) has an interactive mode and a non\-interactive mode. -Interactive mode is turned on automatically when both \f[B]stdin\f[] and -\f[B]stdout\f[] are hooked to a terminal, but the \f[B]\-i\f[] flag and -\f[B]\-\-interactive\f[] option can turn it on in other cases. +bc(1) has an interactive mode and a non-interactive mode. +Interactive mode is turned on automatically when both \f[B]stdin\f[R] +and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag +and \f[B]\[en]interactive\f[R] option can turn it on in other cases. .PP In interactive mode, bc(1) attempts to recover from errors (see the -\f[B]RESET\f[] section), and in normal execution, flushes -\f[B]stdout\f[] as soon as execution is done for the current input. +\f[B]RESET\f[R] section), and in normal execution, flushes +\f[B]stdout\f[R] as soon as execution is done for the current input. .SH TTY MODE .PP -If \f[B]stdin\f[], \f[B]stdout\f[], and \f[B]stderr\f[] are all -connected to a TTY, bc(1) turns on "TTY mode." +If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all +connected to a TTY, bc(1) turns on \[lq]TTY mode.\[rq] .PP TTY mode is required for history to be enabled (see the \f[B]COMMAND -LINE HISTORY\f[] section). -It is also required to enable special handling for \f[B]SIGINT\f[] +LINE HISTORY\f[R] section). +It is also required to enable special handling for \f[B]SIGINT\f[R] signals. .PP The prompt is enabled in TTY mode. @@ -1265,58 +1232,58 @@ The prompt is enabled in TTY mode. TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), -and interactive mode requires only \f[B]stdin\f[] and \f[B]stdout\f[] to -be connected to a terminal. +and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] +to be connected to a terminal. .SH SIGNAL HANDLING .PP -Sending a \f[B]SIGINT\f[] will cause bc(1) to stop execution of the +Sending a \f[B]SIGINT\f[R] will cause bc(1) to stop execution of the current input. -If bc(1) is in TTY mode (see the \f[B]TTY MODE\f[] section), it will -reset (see the \f[B]RESET\f[] section). +If bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), it will +reset (see the \f[B]RESET\f[R] section). Otherwise, it will clean up and exit. .PP -Note that "current input" can mean one of two things. -If bc(1) is processing input from \f[B]stdin\f[] in TTY mode, it will +Note that \[lq]current input\[rq] can mean one of two things. +If bc(1) is processing input from \f[B]stdin\f[R] in TTY mode, it will ask for more input. If bc(1) is processing input from a file in TTY mode, it will stop processing the file and start processing the next file, if one exists, -or ask for input from \f[B]stdin\f[] if no other file exists. +or ask for input from \f[B]stdin\f[R] if no other file exists. .PP -This means that if a \f[B]SIGINT\f[] is sent to bc(1) as it is executing -a file, it can seem as though bc(1) did not respond to the signal since -it will immediately start executing the next file. +This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is +executing a file, it can seem as though bc(1) did not respond to the +signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP -\f[B]SIGTERM\f[] and \f[B]SIGQUIT\f[] cause bc(1) to clean up and exit, -and it uses the default handler for all other signals. -The one exception is \f[B]SIGHUP\f[]; in that case, when bc(1) is in TTY -mode, a \f[B]SIGHUP\f[] will cause bc(1) to clean up and exit. +\f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and +exit, and it uses the default handler for all other signals. +The one exception is \f[B]SIGHUP\f[R]; in that case, when bc(1) is in +TTY mode, a \f[B]SIGHUP\f[R] will cause bc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP -bc(1) supports interactive command\-line editing. -If bc(1) is in TTY mode (see the \f[B]TTY MODE\f[] section), history is +bc(1) supports interactive command-line editing. +If bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), history is enabled. Previous lines can be recalled and edited with the arrow keys. .PP -\f[B]Note\f[]: tabs are converted to 8 spaces. +\f[B]Note\f[R]: tabs are converted to 8 spaces. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP -bc(1) is compliant with the IEEE Std 1003.1\-2017 -(“POSIX.1\-2017”) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) +bc(1) is compliant with the IEEE Std 1003.1-2017 +(\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. -The flags \f[B]\-efghiqsvVw\f[], all long options, and the extensions +The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts -numbers that use a period (\f[B].\f[]) as a radix point, regardless of -the value of \f[B]LC_NUMERIC\f[]. +numbers that use a period (\f[B].\f[R]) as a radix point, regardless of +the value of \f[B]LC_NUMERIC\f[R]. .SH BUGS .PP None are known. @@ -1324,4 +1291,4 @@ Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. -Howard <yzena.tech@gmail.com> and contributors. +Howard <gavin@yzena.com> and contributors. |