.B mtimeout
program sets its exit status as follows.
.TP
-0\(em127
+0\(em127, 255
The child process ran to completion within the given time:
.BR mtimeout 's
exit status is the same as that of the child process.
The child process exited in a way which
.B mtimeout
could not interpret.
+(Whatever status the child exits with will be propagated;
+but if it exits with some status other than these then
+there is a risk that it will be conflict
+with a status used by
+.B mtimeout
+and be misinterpreted.)
.TP
129\(em250
The child process was killed by a signal: the exit status is 128 higher
A system call made by
.B mtimeout
failed unexpectedly: an error message was written to standard error.
-.TP
-255
-Not used.
.
.SH BUGS
Because