[php-src] Issue #8240: Misleading error message on popen() when /bin/sh is missing

Issue: https://github.com/php/php-src/issues/8240 Comment Author: dilyanpalauzov My opinion is that when php calls popen('/bin/sh') and it fails, then php shall verify if /bin/sh exists and if it does not exist, then report the non-existence. Of course fixing this in addidion in LIBC is a good idea. The documentation at https://www.php.net/manual/en/function.popen.php does not emphasize enough that the popen() call is wrapped by /bin/sh call and this has the advantage, that < and > redirections are supposed to work. The disadvantage is, that /bin/sh must exist. Given the spare documentation, < and > redirections are probably not needed, and the invocation of /bin/sh can be removed from php’s code.