home | help 
std::system(3)		       C++ Standard Libary		  std::system(3)

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)
     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 com-
     mand processor
	and returns a nonzero value if and only if the command processor exists.

Parameters
		  character string identifying the command to be run in the com-
     mand
	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.

	An explicit flush of std::cout	is  also  necessary  before  a	call  to
     std::system, if
	the spawned process performs any screen I/O.

Example
     // Run this code

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

      int main()
      {
	  std::system("ls  -l  >test.txt");  // executes 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
	C documentation for
	system

http://cppreference.com 	   2024.06.10			  std::system(3)
home | help