timeout.1: Include exit status documentation in the manual.

diff --git a/timeout.1 b/timeout.1
index b468c87cb4d5efbdc50cb5dc12eca3902aaec10d..9d2c815172e5566cfc8d2b3e84b8aac216562bcf 100644 (file)
--- a/timeout.1
+++ b/timeout.1
@@ -59,6 +59,50 @@ A signal may be given numerically (e.g., 9 for
 .BR SIGKILL )
 or by name (e.g.,
 .BR KILL ).
+.PP
+The
+.B timeout
+program sets its exit status as follows.
+.TP
+0\(em127
+The child process ran to completion within the given time:
+.BR timeout 's
+exit status is the same as that of the child process.
+.TP
+128
+The child process exited in a way which
+.B timeout
+could not interpret.
+.TP
+129\(em250
+The child process was killed by a signal: the exit status is 128 higher
+than the signal number.  If
+.B timeout
+had to kill the child because it took too long, then its exit status
+will be like this.
+.TP
+251
+The child took too long and couldn't be killed:
+.B timeout
+gave up waiting.
+.TP
+252
+The target program couldn't be started: an error message was written to
+standard error.
+.TP
+253
+The
+.B timeout
+program couldn't parse the arguments provided to it: an error message
+was written to standard error.
+.TP
+254
+A system call made by
+.B timeout
+failed unexpectedly: an error message was written to standard error.
+.TP
+255
+Not used.
 .
 .SH BUGS
 Because