Doc #80230 [Opn->Ver]: Doc for exec specifies & (reference) param, fails

Edit report at https://bugs.php.net/bug.php?id=80230&edit=1 ID: 80230 Updated by: cmb@php.net Reported by: per at perit dot se Summary: Doc for exec specifies & (reference) param, fails -Status: Open +Status: Verified Type: Documentation Problem Package: Documentation problem Operating System: Linux PHP Version: Irrelevant Block user comment: N Private report: N New Comment: What Rowan said. And yes, there should be an example. Note that there is also an appendix on "How to read a function definition (prototype)"[1] > "(PHP 4, PHP 5, PHP 7)" That just means that function is available for PHP 4, 5 and 7; it does not imply that it worked exactly the same in older versions. In fact, the manual currently is supposed to document only PHP 7 (there is few info about PHP 8, and still some info about PHP 5, though). [1] <https://www.php.net/manual/en/about.prototypes.php> Previous Comments: ------------------------------------------------------------------------ [2020-10-13 20:04:52] rowan dot collins at gmail dot com The documentation is showing you the *signature* of the function, not the *usage*. An actual declaration in userland would in fact look something like this: function exec (string $command, ?array &$output=null, ?int &$return_var=null): string { .... } The manual page could do with an example of using those params though, which would look something like this: $output=null; $retval=null; exec('whoami', $output, $retval); echo "Returned with status $retval and output $output"; ------------------------------------------------------------------------ [2020-10-13 19:45:20] per at perit dot se Description: ------------ --- From manual page: https://php.net/function.exec --- The documentation specifies syntax exec ( string $command [, array &$output [, int &$return_var ]] ) : string This syntax breaks PHP, and according to numerous internet articles like https://stackoverflow.com/questions/8971261/php-5-4-call-time-pass-by-reference-easy-fix-available explaining it has been so a while: > As of PHP 5.3.0, you will get a warning saying that "call-time pass-by-reference" is > deprecated when you use & in foo(&$a);. Please update the documentation with correct syntax, and if/when it differs for specific versions, please note the version and change in question - now it incorrectly claims to be valid for "(PHP 4, PHP 5, PHP 7)" Test script: --------------- $ cat > test-ref-arg.php <?php exec ( "pwd", &$output ); echo "Got output: "; var_dump($output); $ php test-ref-arg.php PHP Fatal error: Call-time pass-by-reference has been removed in /home/xx/IMPORT/test-ref-arg on line 2 /opt/rh/rh-php73/root/bin/php test-ref-arg.php PHP Parse error: syntax error, unexpected '&', expecting ')' in /home/xx/test-ref-arg.php on line 2 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=80230&edit=1