This problem has been annoying me for a while. So I wrote a patch.
The attached patch provides an option for watch to monitor stderr as
well as stdout. [I think that behavior should be the default, but for
now, I've just made it an option.] It also provide an option for
watch to beep if the command fails.
I emailed it to the procps feedback list a couple of days ago, and
haven't heard back yet. So I decided to open a debian bug for
tracking purposes. . . and found there already are a bunch.
Looks like 481679 is also a dup of this bug.
- Morty
Binary files procps-3.2.7-orig/.watch.c.swp and procps-3.2.7/.watch.c.swp differ
diff -Nur procps-3.2.7-orig/watch.1 procps-3.2.7/watch.1
--- procps-3.2.7-orig/watch.1 2003-02-09 02:05:25.000000000 -0500
+++ procps-3.2.7/watch.1 2008-08-06 07:01:05.000000000 -0400
@@ -3,7 +3,7 @@
watch \- execute a program periodically, showing output fullscreen
.SH SYNOPSIS
.B watch
-.I [\-dhvt] [\-n <seconds>] [\-\-differences[=cumulative]] [\-\-help]
[\-\-interval=<seconds>] [\-\-no\-title] [\-\-version] <command>
+.I [\-bdhvst] [\-n <seconds>] [\-\-beep] [\-\-differences[=cumulative]]
[\-\-errors-too] [\-\-help] [\-\-interval=<seconds>] [\-\-no\-title]
[\-\-version] <command>
.SH DESCRIPTION
.BR watch
runs
@@ -28,7 +28,15 @@
or
.I --no-title
option turns off the header showing the interval, command, and current
-time at the top of the display, as well as the following blank line.
+time at the top of the display, as well as the following blank line. The
+.I -b
+or
+.I --beep
+option causes the command to beep if it has a non-zero exit. The
+.I -s
+or
+.I --errors-too
+option causes error output to be handled just like normal output.
.PP
.BR watch
will run until interrupted.
@@ -84,4 +92,5 @@
.B watch
was written by Tony Rems <[EMAIL PROTECTED]> in 1991, with mods and
corrections by Francois Pinard. It was reworked and new features added by
-Mike Coleman <[EMAIL PROTECTED]> in 1999.
+Mike Coleman <[EMAIL PROTECTED]> in 1999. The beep and errors-too features
were
+added by Morty Abzug <[EMAIL PROTECTED]> in 2008.
diff -Nur procps-3.2.7-orig/watch.c procps-3.2.7/watch.c
--- procps-3.2.7-orig/watch.c 2006-06-17 05:18:38.000000000 -0400
+++ procps-3.2.7/watch.c 2008-08-06 07:06:06.000000000 -0400
@@ -8,6 +8,7 @@
* Mike Coleman <[EMAIL PROTECTED]>.
*
* Changes by Albert Cahalan, 2002-2003.
+ * errors-too and beep options added by Morty Abzug, 2008
*/
#define VERSION "0.2.0"
@@ -35,13 +36,15 @@
{"differences", optional_argument, 0, 'd'},
{"help", no_argument, 0, 'h'},
{"interval", required_argument, 0, 'n'},
+ {"errors-too", no_argument, 0, 's'},
+ {"beep", no_argument, 0, 'b'},
{"no-title", no_argument, 0, 't'},
{"version", no_argument, 0, 'v'},
{0, 0, 0, 0}
};
static char usage[] =
- "Usage: %s [-dhntv] [--differences[=cumulative]] [--help] [--interval=<n>]
[--no-title] [--version] <command>\n";
+ "Usage: %s [-bdhnstv] [--beep] [--differences[=cumulative]] [--errors-too]
[--help] [--interval=<n>] [--no-title] [--version] <command>\n";
static char *progname;
@@ -140,17 +143,25 @@
int optc;
int option_differences = 0,
option_differences_cumulative = 0,
+ option_errors_too = 0,
+ option_beep = 0,
option_help = 0, option_version = 0;
double interval = 2;
char *command;
int command_length = 0; /* not including final \0 */
+ int pipefd[2];
+ int status;
+ pid_t child;
setlocale(LC_ALL, "");
progname = argv[0];
- while ((optc = getopt_long(argc, argv, "+d::hn:vt", longopts, (int *)
0))
+ while ((optc = getopt_long(argc, argv, "+bd::hn:vst", longopts, (int *)
0))
!= EOF) {
switch (optc) {
+ case 'b':
+ option_beep = 1;
+ break;
case 'd':
option_differences = 1;
if (optarg)
@@ -159,6 +170,9 @@
case 'h':
option_help = 1;
break;
+ case 's':
+ option_errors_too = 1;
+ break;
case 't':
show_title = 0;
break;
@@ -191,11 +205,13 @@
if (option_help) {
fprintf(stderr, usage, progname);
+ fputs(" -b, --beep\t\t\t\tbeep if the command has a non-zero
exit\n", stderr);
fputs(" -d, --differences[=cumulative]\thighlight changes
between updates\n", stderr);
fputs("\t\t(cumulative means highlighting is cumulative)\n",
stderr);
fputs(" -h, --help\t\t\t\tprint a summary of the options\n",
stderr);
fputs(" -n, --interval=<seconds>\t\tseconds to wait between
updates\n", stderr);
fputs(" -v, --version\t\t\t\tprint the version number\n",
stderr);
+ fputs(" -s, --errors-too\t\t\tredirects errors as well\n",
stderr);
fputs(" -t, --no-title\t\t\tturns off showing the header\n",
stderr);
exit(0);
}
@@ -261,11 +277,50 @@
free(header);
}
- if (!(p = popen(command, "r"))) {
- perror("popen");
+ /* allocate pipes */
+ if (pipe(pipefd)<0) {
+ perror("pipe");
+ do_exit(7);
+ }
+
+ /* flush stdout and stderr, since we're about to do fd stuff */
+ fflush(stdout);
+ fflush(stderr);
+
+ /* fork and exec */
+ child=fork();
+
+ if (child<0) { /* fork error */
+ perror("fork");
do_exit(2);
+ } else if (child==0) { /* in child */
+ close (pipefd[0]);
+ close (1);
+ if (dup2 (pipefd[1], 1)<0) {
+ perror("dup2");
+ exit(3);
+ }
+ if (option_errors_too) {
+ close(2);
+ dup2(1, 2);
+ }
+ /* this should use execvp, but the watch manpage
promises quoting */
+ status=system(command);
+ if (!WIFEXITED(status)) {
+ exit(1);
+ } else {
+ exit(WEXITSTATUS(status));
+ }
}
+ /* otherwise, we're in parent */
+ close(pipefd[1]); /* close write side of pipe */
+ if ((p=fdopen(pipefd[0], "r"))==NULL) {
+ perror("fdopen");
+ do_exit(5);
+ }
+
+
for (y = show_title; y < height; y++) {
int eolseen = 0, tabpending = 0;
for (x = 0; x < width; x++) {
@@ -313,7 +368,18 @@
oldeolseen = eolseen;
}
- pclose(p);
+ fclose(p);
+
+ /* harvest child process and get status */
+ if (waitpid(child, &status, 0)<0) {
+ perror("waitpid");
+ do_exit(8);
+ };
+
+ /* if child process exited in error, beep */
+ if (option_beep && (!WIFEXITED(status) || WEXITSTATUS(status)))
{
+ beep();
+ }
first_screen = 0;
refresh();
