Used to execute external programs (e.g. system commands).
Take at least one parameter: the command /program to be executed.
exec() runs the command/program and sends back the last line output from that program as its return value.
exec( "command", $output, $return ) ;
Optional parameters:
- 2nd parameter will contain the output of the command as an array with one line per element.
- 3rd parameter contains the return value of the command.
<?php exec("ls -a", $output, $return); echo "The command ls - a returned $return, and output:<br>"; echo "<pre>"; print_r( $output ); echo "</pre>"; ?>
passthru() runs the command/program and displays all of the raw output directly to the screen.
passthru( "command", $return ) ;
Optional parameters:
- 2nd parameter contains the return value of the command.
<?php echo "The command ls - a in passthru() displays: <br>"; passthru("ls -a") ; ?>
system() runs the command/program and displays the raw output directly to the screen.
system( "command", $return ) ;
<?php echo "The command ls - a in system() displays: <br>"; system("ls -a") ; ?>