I have an application on my server that is called leaf.exe, that haves two arguments needed to run, they are: inputfile and outputfile, that will be like this example:
pnote.exe input.pnt output.txt
The executable is at exec/, inputfile is at upload/ and outputfile is on compiled/. But I need that a PHP could run the application like that, then I want to know:
How could I do this on a server that have exec() disabled and I can't turn it on, because I don't have privileges to do it?
How could I echo the output of the program?
The exec function is probably what you're looking for: PHP: exec - Manual
There are a fair amount of ways to do this. It partly depends on how your executables act and what they return. Have a look at System Program Execution. Hober suggests exec(), and that may be right. Another possibility may be passthru()
Related
Is there any reason why I can not complied files in PHP's shell_exec/exec/system function?
Example of something that does work in command line and PHP's shell_exec function:
<?php
$data = shell_exec("ls");
echo $data;
?>
Example of something that does not work in PHP's shell_exec function but will work in command line (I can confirm that):
<?php
$data = shell_exec("./c-compiled-file argv1 argv2 argv3");
echo $data;
?>
Is there anything I can do on my server so this will work? I've looked everywhere and no solutions I found fixed the problem. The compiled file is in the same directory as the PHP script as well, it just won't execute it. Also if you're asking, yes I have tried this with SSH2 and it still will not execute.
Also PHP is not in safe mode and NO functions are disabled.
Some common glitches when executing external commands from PHP that work fine from shell:
Command uses relative paths but PHP is launched from an arbitrary location:
Use getcwd() / chdir() to get/set working directory
PHP and shell run with different user credentials. This is often the case when PHP runs through a web server.
PHP and shell run different commands. Many people call stuff like exec("foo $bar") and doesn't even check what "foo $bar" contains.
No error checking is done. The bare minimum is to capture and print standard output, standard error, status code and, of course, all PHP error messages including warnings and notices.
You can redirect stderr to sdtout
You can use a PHP function that allows to capture more information, such as exec()
The web server is disallowed to execute the command at operating system level.
Lookout for SELinux or similar tools.
Just a guess, but the binary you're trying to execute might not have the proper permissions. Prepeding it with ./ in the command line forces it to execute, but PHP probably strips that for security purposes. Try this:
chmod +x c-compiled-file
You want to use system in the second case, and not shell_exec.
system executes an external program and displays the output.
shell_exec executes a command via shell and returns the complete output as a string.
and for good measure:
exec simply executes an external program.
Furthermore you want to make sure your external program is executable and (though you have stated it, I'll restate this) has execute permissions for the user which is running the web server. You also want to make sure the directory your external program is running in has the ability to write to its directory or /tmp or whatever output directory you have set.
Finally you should always use absolute paths for executing things like this in cron or php or whatever... so don't use ./c-compiled-file argv1 argv2 argv3, but instead use /home/username/c-compiled-file argv1 argv2 argv3 or whatever the full path is.
Here's my code to create a new at job...
system('echo \'php -f /path/to/my/php/file.php\' | at 1700');
I thought this would be simple and would just work but alas, nothing happens!
When I run echo \'php -f /path/to/my/php/file.php\' | at 1700 via ssh everything works as expected.
Is this a permissions problem? I.e PHP isn't allowed to create new at jobs?
Just FYI you have to make sure that you are allowed to execute system commands from your PHP scripts.
A lot of servers have this feature disabled.
However, if you want to turn this back on I believe you can do so in the php.ini file, you would have to turn safe_mode to off.
When allowing user-supplied data to be passed to this function, use escapeshellarg() or escapeshellcmd() to ensure that users cannot trick the system into executing arbitrary commands.
If a program is started with this function, in order for it to continue running in the background, the output of the program must be redirected to a file or another output stream. Failing to do so will cause PHP to hang until the execution of the program ends.
Note: When safe mode is enabled, you can only execute files within the safe_mode_exec_dir. For practical reasons, it is currently not allowed to have .. components in the path to the executable.
<?php
exec("whoami");
?>
I can be more explicit with the code . Although When I'm trying to call the php file with my browser nothing happens (of course I'm using apache and the whole).
Note : The safe_mode is activated, I'm using php5, php interpreter seems to be nice when running other functions, I'm a ubuntu user.
Then what is wrong?
I think you're looking for the echo function. Executing whoami using the exec function will run the program but show you nothing… you want to spit out the result too.
echo exec("whoami");
You have to echo the output of the exec command somewhere.
PHP documentation for exec function contains the example with whoami, look at the echo.
Right in the docs for exec:
When safe mode is enabled, you can only execute files within the safe_mode_exec_dir. For practical reasons, it is currently not allowed to have .. components in the path to the executable.
If possible, turn off safe mode. Safes you lots of headaches.
Otherwise, is the php file owned by the same user that Apache runs as?
On Ubuntu, this will usually be www-data.
Try:
sudo chown www-data /path/to/you/script.php
Then run again.
Occasionally my media server goes down and I'm wondering if it's possible to start it remotely using php to check the port and if it's not running invoke cron (or some other way) to run a shell command. Is this possible because this is not a strong area for me. Here's the process I use with PuTTy.
login to shell
cd to source/red5/dist
screen
./red5.sh
CTRL-A then D to detach
logout
Simplest thing is to write a shell script. And then login to remote console via PHP.
shell_exec: execute a shell command and returns the output as string.
exec: just executes an external program
A simple way to achieve what you want is to run this in screen:
while /bin/true ; do ./red5.sh ; done
If you can write a shell script that does what you need, then PHP's has exec(), system() and passthru() for you.
PHP actually has a special operator for executing shell commands, the backtick:
`cd source/red5/dist`
will go to the specified directory. (But I don't know much about shell, so I can't implement you the whole thing.)
If you need much control over the execution (I don't know whether you need here) use proc_open.
you can use corn job on php and put all command on .sh file and run like this
59 11 * * 1,2,3,4,5 root command file.sh?token
something like this ,it will be save
There is more than one good answer here, but you should opt for executing the init script for red5 instead of the .sh or .bat. There are pre-made init scripts here: http://code.google.com/p/bigbluebutton/downloads/detail?name=red5&can=2&q= and here: http://www.videowhisper.com/forum.php?ftid=48&t=init-file-red5-linux-installations-red5-linux-init.d-chkconfig
I have a program that returns a comma-separated string of numbers after doing some background processing. I intended to run this in symfony using shell_exec; however, all I get is NULL (revealed through a var_dump(). I tried the following debugging steps.
I ran the file (it's a PHP class) through a command-line lime unit test in Symfony - it works and gives the correct result there.
Just to check, I tried a simple command ls -l at the same place to see whether I would get anything. Again, I had the same problem - the var_dump in the browser showed NULL, but it worked through the command line.
What could be the problem? Are there restrictions on running shell_exec() in a browser?
EDIT: Just to clarify, shell_exec() commands work when I run them as standalone php scripts on the web server (for example, by putting them in my document root. They don't seem to be working under the symfony framework, for some reason.
I finally solved it, and it turned out to be something quite simple, and quite unrelated.
The shell command I was running was in this format: face_query -D args. I didn't realize that Apache would be executing PHP as user www-data and thus the program face_query wouldn't be in the PATH (the directory is actually ~/bin). Changing the program name to the full path of the program solved it.
I also gather from this that only commands which www-data has permission to execute can be run. In this case, www-data is in the same group as my user, but it might be a problem otherwise.
Have you tried using exec? Or one of the other variants. I am never sure of which one to use and always lump with exec.
http://uk.php.net/manual/en/function.exec.php
Is your web server running php in safe mode?
Note: This function is disabled when PHP is running in safe mode.
From: http://php.net/manual/en/function.shell-exec.php