How to get output from executable file in php

Question

I can't get output from executable file (a.out) via php. my php code is :

$file = "/path/main.cpp";
$command="cd $path && c++ -lm ".$file;
exec($command);
$output = exec("cd $path && ./a.out");
exec("cd $path && ./a.out > res.txt");
var_dump($output);

all commands is executed but, I'm getting empty value;

exec("cd $path && ./a.out > res.txt");

this command also executed, res.txt was created in folder, but empty file. How to solve this problem? My OS is CentOS 7

Seems like you want [`popen`](https://www.php.net/manual/en/function.popen.php). — Some programmer dude, Nov 18 '19 at 08:36
Regarding the "empty file" from the redirection, are you sure that the program actually generates any output? Or that the compilation succeeded and the `a.out` program existing? — Some programmer dude, Nov 18 '19 at 08:37
Try capturing the error output as well, see if it's failing (https://stackoverflow.com/questions/3863699/php-exec-not-returning-error-message-in-output). — Nigel Ren, Nov 18 '19 at 08:41

score 0 · Answer 1 · answered Nov 18 '19 at 08:46

0

In order to get the output of a command with PHP, you can use the shell_exec function:

shell_exec

shell_exec — Execute command via shell and return the complete output as a string

So, try this:

$output = shell_exec("cd $path && ./a.out");

answered Nov 18 '19 at 08:46

user2342558

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sh: ./a.out: Permission denied – Bakhodir Ismatov Nov 18 '19 at 08:53
@BakhodirIsmatov so the problem is another... when you resolve it, `shell_exec` will do what you need – user2342558 Nov 18 '19 at 09:08
can apache run a.out ? – Bakhodir Ismatov Nov 18 '19 at 09:43
@BakhodirIsmatov try to run it from terminal if you can, otherwise try to run this in `shell_exec`: `echo shell_exec('echo "it works";');`. Because I don't know what does `a.out` contain, I can't help you on that. – user2342558 Nov 18 '19 at 15:52

How to get output from executable file in php

1 Answers1