What does execve() do?

c++ c linux execve
Nosrettap picture Nosrettap · Apr 9, 2012 · Viewed 20.7k times · Source

What exactly does execve() do? I've tried looking at the documentation (http://linux.die.net/man/2/execve) but given that I'm very new to linux and this sort of programming it doesn't make a lot of sense. What I want to do is be able to execute this command: 

nc -l -p someport -e /bin/sh

Can I do something like the following (where someport is a number such as 4444)

char *command[2];
command[0] = "nc -l -p someport -e /bin/sh"
execve(command[0], name, NULL);

Answer

Jerry Coffin picture Jerry Coffin · Apr 9, 2012

execve replaces the current process with a new process, running the command you specified as its first argument.

Chances are pretty decent that you want execvp or execlp instead -- you haven't mentioned anything about wanting to provide the environment for the child, but from the looks of things you probably do want the path searched to find the executable you're using.

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