what is the difference between popen() and system() in C

c system popen
Syntax_Error picture Syntax_Error · Dec 16, 2011 · Viewed 24.8k times · Source

I want to execute a binary within my C code. Which is better to execute with? popen() or system()

EDIT: I tried to use system, but the process executing seems to get stuck in the end and does not return to my code.

Any suggestions on what to do?

Thanks

Answer

Kerrek SB picture Kerrek SB · Dec 16, 2011

popen() gives you control over the process's input or output file streams. system() doesn't. If you don't need to access the process's I/O, you can use system() for simplicity.

system() is in C89 and C99; popen() is Posix only (though the Windows API also has one).

Both functions invoke some form of a shell to execute the command (e.g. /bin/sh on Linux, and probably cmd.exe on Windows). If you want to execute an executable file directly and you are on Posix, you can also look at the exec*-family of functions in conjuction with fork() (since exec() replaces the current process).

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