Author: cem Date: Sat Mar 4 22:38:10 2017 New Revision: 314685 URL: https://svnweb.freebsd.org/changeset/base/314685
Log: ps(1): Only detect terminal width if stdout is a tty If stdout isn't a tty, use unlimited width output rather than truncating to 79 characters. This is helpful for shell scripts or e.g., 'ps | grep foo'. This hardcoded width has some history: In The Beginning of History[0], the width of ps was hardcoded as 80 bytes. In 1985, Bloom@ added detection using TIOCGWINSZ on stdin.[1] In 1986, Kirk merged a change to check stdout's window size instead. In 1990, the fallback checks to stderr and stdin's TIOCGWINSZ were added by Marc@, with the commit message "new version."[2] OS X Darwin has a very similar modification to ps(1), which simply sets UNLIMITED for all non-tty outputs.[3] I've chosen to respect COLUMNS instead of behaving identically to Darwin here, but I don't feel strongly about that. We could match OS X for parity if that is desired. [0]: https://svnweb.freebsd.org/csrg/bin/ps/ps.c?annotate=1065 [1]: https://svnweb.freebsd.org/csrg/bin/ps/ps.c?r1=18105&r2=18106 [2]: https://svnweb.freebsd.org/csrg/bin/ps/ps.c?r1=40675&r2=40674&pathrev=40675 [3]: https://opensource.apple.com/source/adv_cmds/adv_cmds-168/ps/ps.c.auto.html PR: 217159 Reported by: Deepak Nagaraj <n.deepak at gmail.com> Modified: head/bin/ps/ps.c Modified: head/bin/ps/ps.c ============================================================================== --- head/bin/ps/ps.c Sat Mar 4 22:23:59 2017 (r314684) +++ head/bin/ps/ps.c Sat Mar 4 22:38:10 2017 (r314685) @@ -194,6 +194,8 @@ main(int argc, char *argv[]) if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0') termwidth = atoi(cols); + else if (!isatty(STDOUT_FILENO)) + termwidth = UNLIMITED; else if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, (char *)&ws) == -1 && ioctl(STDERR_FILENO, TIOCGWINSZ, (char *)&ws) == -1 && ioctl(STDIN_FILENO, TIOCGWINSZ, (char *)&ws) == -1) || _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
