std::system (3) - Linux Man Pages

std::system: std::system

NAME

std::system - std::system

Synopsis


Defined in header <cstdlib>
int system( const char* command );


Calls the host environment's command processor (e.g. /bin/sh, cmd.exe, command.com) with the parameter command. Returns an implementation-defined value (usually the value that the invoked program returns).
If command is a null pointer, checks if the host environment has a command processor and returns a nonzero value if and only if the command processor exists.

Parameters


command - character string identifying the command to be run in the command processor. If a null pointer is given, command processor is checked for existence

Return value


Implementation-defined value. If command is a null pointer, returns a nonzero value if and only if the command processor exists.

Notes


On POSIX systems, the return value can be decomposed using WEXITSTATUS_and_WSTOPSIG
The related POSIX function popen makes the output generated by command available to the caller.

Example


// Run this code


  #include <cstdlib>
  #include <fstream>
  #include <iostream>


  int main()
  {
      std::system("ls -l >test.txt"); // execute the UNIX command "ls -l >test.txt"
      std::cout << std::ifstream("test.txt").rdbuf();
  }

Possible output:


  total 16
  -rwxr-xr-x 1 2001 2000 8859 Sep 30 20:52 a.out
  -rw-rw-rw- 1 2001 2000 161 Sep 30 20:52 main.cpp
  -rw-r--r-- 1 2001 2000 0 Sep 30 20:52 test.txt

See also