3 files changed, 89 insertions, 0 deletions

diff --git a/bin/procctl/Makefile b/bin/procctl/Makefile
new file mode 100644
index 000000000000..ceb3df3a9a93
--- /dev/null
+++ b/bin/procctl/Makefile
@@ -0,0 +1,5 @@
+PROG=	procctl
+LDFLAGS += -static
+
+.include <bsd.prog.mk>
+
diff --git a/bin/procctl/procctl.1 b/bin/procctl/procctl.1
new file mode 100644
index 000000000000..8af32da30fd8
--- /dev/null
+++ b/bin/procctl/procctl.1
@@ -0,0 +1,29 @@
+.Dd Nov 23, 1997
+.Dt PROCCTL 1
+.Os FreeBSD
+.Sh NAME
+.Nm \&procctl
+.Nd clear procfs event flags
+.Sh Synopsis
+.Nm \&procctl
+.Ar command
+.Ar [...]
+.Sh DESCRIPTION
+.Nm \&procctl
+clears the
+.Xr procfs 5
+event mask used by
+.Xr truss 1 .
+This can be used in the event that a process is left stranded, since
+the
+.Xr procfs 5
+events result in a non-killable process.
+The options are a list of process ID's;
+.Nm \&procctl
+goes through the list and clears the event masks for each specified process.
+.Xr truss 1 ,
+.Xr procfs 5
+.Sh HISTORY
+The
+.Nm procctl
+command was written by Sean Eric Fagan for FreeBSD.
diff --git a/bin/procctl/procctl.c b/bin/procctl/procctl.c
new file mode 100644
index 000000000000..2578c477b69d
--- /dev/null
+++ b/bin/procctl/procctl.c
@@ -0,0 +1,55 @@
+/*
+ * procctl -- clear the event mask, and continue, any specified processes.
+ * This is largely an example of how to use the procfs interface; however,
+ * for now, it is also sometimes necessary, as a stopped process will not
+ * otherwise continue.  (This will be fixed in a later version of the
+ * procfs code, almost certainly; however, this program will still be useful
+ * for some annoying circumstances.)
+ */
+/*
+ * $Id$
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <err.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/pioctl.h>
+
+main(int ac, char **av) {
+  int fd;
+  int i;
+  unsigned int mask;
+  char **command;
+  struct procfs_status pfs;
+
+  for (i = 1; i < ac; i++) {
+    char buf[32];
+
+    sprintf(buf, "/proc/%s/mem", av[i]);
+    fd = open(buf, O_RDWR);
+    if (fd == -1) {
+      if (errno == ENOENT)
+	continue;
+      fprintf(stderr, "%s:  cannot open pid %s:  %s\n",
+	      av[0], av[i], strerror(errno));
+      continue;
+    }
+    mask = ~0;
+    if (ioctl(fd, PIOCBIC, &mask) == -1) {
+      fprintf(stderr, "%s:  cannot clear process %s's event mask: %s\n",
+	      av[0], av[i], strerror(errno));
+    }
+    mask = 0;
+    if (ioctl(fd, PIOCCONT, &mask) == -1 && errno != EINVAL) {
+      fprintf(stderr, "%s:  cannot continue process %s:  %s\n",
+	      av[0], av[i], strerror(errno));
+    }
+    close(fd);
+  }
+  return 0;
+}