diff options
Diffstat (limited to 'newctime.3.txt')
| -rw-r--r-- | newctime.3.txt | 76 |
1 files changed, 33 insertions, 43 deletions
diff --git a/newctime.3.txt b/newctime.3.txt index be0cb316d21d..82fdf5e69a00 100644 --- a/newctime.3.txt +++ b/newctime.3.txt @@ -7,52 +7,40 @@ NAME SYNOPSIS #include <time.h> - [[deprecated]] char *ctime(time_t const *clock); - - /* Only in POSIX.1-2017 and earlier. */ - char *ctime_r(time_t const *clock, char *buf); - - double difftime(time_t time1, time_t time0); - - [[deprecated]] char *asctime(struct tm const *tm); - - /* Only in POSIX.1-2017 and earlier. */ - char *asctime_r(struct tm const *restrict tm, - char *restrict result); - struct tm *localtime(time_t const *clock); - struct tm *localtime_r(time_t const *restrict clock, struct tm *restrict result); - struct tm *localtime_rz(timezone_t restrict zone, time_t const *restrict clock, struct tm *restrict result); struct tm *gmtime(time_t const *clock); - struct tm *gmtime_r(time_t const *restrict clock, struct tm *restrict result); time_t mktime(struct tm *tm); - time_t mktime_z(timezone_t restrict zone, struct tm *restrict tm); + double difftime(time_t time1, time_t time0); + + [[deprecated]] char *asctime(struct tm const *tm); + [[deprecated]] char *ctime(time_t const *clock); + + /* Only in POSIX.1-2017 and earlier. */ + char *ctime_r(time_t const *clock, char *buf); + char *asctime_r(struct tm const *restrict tm, + char *restrict result); + cc ... -ltz DESCRIPTION - The ctime function converts a long integer, pointed to by clock, and - returns a pointer to a string of the form - Thu Nov 24 18:22:48 1986\n\0 - Years requiring fewer than four characters are padded with leading - zeroes. For years longer than four characters, the string is of the - form - Thu Nov 24 18:22:48 81986\n\0 - with five spaces before the year. These unusual formats are designed - to make it less likely that older software that expects exactly 26 - bytes of output will mistakenly output misleading values for out-of- - range years. + The localtime and gmtime functions convert an integer, pointed to by + clock, and return pointers to "tm" structures, described below. If the + integer is out of range for conversion, these functions return a null + pointer. The localtime function corrects for the time zone and any + time zone adjustments (such as Daylight Saving Time in the United + States). The gmtime function converts to Coordinated Universal Time. The *clock timestamp represents the time in seconds since 1970-01-01 00:00:00 Coordinated Universal Time (UTC). The POSIX standard says @@ -62,21 +50,6 @@ DESCRIPTION are some other flavor of Universal Time (UT). Some implementations support leap seconds, in contradiction to POSIX. - The ctime function is deprecated starting in C23. Callers can use - localtime_r and strftime instead. - - The localtime and gmtime functions return pointers to "tm" structures, - described below. The localtime function corrects for the time zone and - any time zone adjustments (such as Daylight Saving Time in the United - States). - - The gmtime function converts to Coordinated Universal Time. - - The asctime function converts a time value contained in a "tm" - structure to a string, as shown in the above example, and returns a - pointer to the string. This function is deprecated starting in C23. - Callers can use strftime instead. - The mktime function converts the broken-down time, expressed as local time, in the structure pointed to by tm into a calendar time value with the same encoding as that of the values returned by the time function. @@ -104,6 +77,23 @@ DESCRIPTION The difftime function returns the difference between two calendar times, (time1 - time0), expressed in seconds. + The asctime function converts a time value contained in a "tm" + structure to a pointer to a string of the form + Thu Nov 24 18:22:48 1986\n\0 + Years requiring fewer than four characters are padded with leading + zeroes. For years longer than four characters, the string is of the + form + Thu Nov 24 18:22:48 81986\n\0 + with five spaces before the year. This unusual format is designed to + make it less likely that older software that expects exactly 26 bytes + of output will mistakenly output misleading values for out-of-range + years. This function is deprecated starting in C23. Callers can use + strftime instead. + + The ctime function is equivalent to calliing localtime and then calling + asctime on the result. Like asctime, this function is deprecated + starting in C23. Callers can use localtime and strftime instead. + The ctime_r, localtime_r, gmtime_r, and asctime_r functions are like their unsuffixed counterparts, except that they accept an additional argument specifying where to store the result if successful. The |