Implementation exec-alike function #30

Aer misses some kind of exec() or system(). It might be very useful, especially on embedded devices to interact with system and other software. I think we should implements it before 1.0.

Generally speaking, I think this is good idea.

int exec(string $cmd, [string &$output]);

First argument contains command to execute, second parameter will contains output from command execution if passed by reference.

Function returns -1 if any error ocurred, or command return value.

Some other ideas?

Should we get also a potential error reason ? (like from errno for example)

What kind of error do we expect? If application launched throw error it should be saved in $output and its return code should be returned by exec() function. Do we need something more?

All exec* sets errno internally, was just wondering if we should return the string error as third parameter (optional).

Not forcing anything here, it is good as is too.

This is true. I just wonder in which case it could be useful, because actually I don't find a reason why it might fail, except when exec() would be disabled.