freebsd man page for setproctitle

SETPROCTITLE(3) 					   BSD Library Functions Manual 					   SETPROCTITLE(3)

NAME
     setproctitle -- set process title

SYNOPSIS
     #include <sys/types.h>
     #include <unistd.h>

     void
     setproctitle(const char *fmt, ...);

DESCRIPTION
     The setproctitle() library routine sets the process title that appears on the ps(1) command.

     The title is set from the executable's name, followed by the result of a printf(3) style expansion of the arguments as specified by the fmt
     argument.	If the fmt argument begins with a ``-'' character, the executable's name is skipped.

     If fmt is NULL, the process title is restored.

EXAMPLES
     To set the title on a daemon to indicate its activity:

	   setproctitle("talking to %s", inet_ntoa(addr));

SEE ALSO
     ps(1), w(1), kvm(3), kvm_getargv(3), printf(3)

STANDARDS
     The setproctitle() function is implicitly non-standard.  Other methods of causing the ps(1) command line to change, including copying over
     the argv[0] string are also implicitly non-portable.  It is preferable to use an operating system supplied setproctitle() if present.

     Unfortunately, it is possible that there are other calling conventions to other versions of setproctitle(), although none have been found by
     the author as yet.  This is believed to be the predominant convention.

     It is thought that the implementation is compatible with other systems, including NetBSD and BSD/OS.

HISTORY
     The setproctitle() function first appeared in FreeBSD 2.2.  Other operating systems have similar functions.

AUTHORS
     Peter Wemm <peter@FreeBSD.org> stole the idea from the Sendmail 8.7.3 source code by Eric Allman <eric@sendmail.org>.

BUGS
     Never pass a string with user-supplied data as a format without using '%s'.  An attacker can put format specifiers in the string to mangle
     your stack, leading to a possible security hole.  This holds true even if the string was built using a function like snprintf(), as the
     resulting string may still contain user-supplied conversion specifiers for later interpolation by setproctitle().

     Always use the proper secure idiom:

	   setproctitle("%s", string);

BSD
								 December 16, 1995							       BSD