php调用bash问题

Question

I have this simple php script

<?php
echo '<pre>';

// Outputs all the result of shellcommand "ls", and returns
// the last output line into $last_line. Stores the return value
// of the shell command in $retval.
$last_line = $output = system ("~/public_html/cgi-bin/srch.sh &> ~/public_html/errors.txt",$retval);

// Printing additional info
echo '
</pre>
<hr />Last line of the output: ' . $last_line . '
<hr />Return value: ' . $retval;
?>

Which relies on srch.sh:

#!/bin/bash

for i in ~/mail/home/user/mail/domain.com/josh/cur/*
do
grep -i Value $i . &> ~/public_html/yesno.txt;
done

However, all that is display in the b rowser is Retval 1, and no error gets recorded to either of the textfiles. Have I mixed stderr and stdout incorrectly, or missed something else?

Answer 1

$last_line = $output = system ("~/public_html/cgi-bin/srch.sh &> ~/public_html/errors.txt",$retval);

The above line runs srch.sh and redirects all the output it produces to errors.txt. Therefore, there is no output left to assign to $output (and $last_line). You'll find your last line (together with the rest of the output) in errors.txt.

If not, try running the shell script directly and see if it produces any output at all.