system


function
<cstdlib>
int system ( const char * command );

Execute system command

Invokes the command processor to execute a command. Once the command execution has terminated, the processor gives the control back to the program, returning an int value, whose interpretation is system-dependent.

The function call also be used with NULL as argument to check whether a command processor exists.

Parameters

command
C string containing the system command to be executed.


Return Value

The value returned when the argument passed is not NULL, depends on the running environment specifications. In many systems, 0 is used to indicate that the command was succesfully executed and other values to indicate some sort of error.
When the argument passed is NULL, the function returns a nonzero value if the command processor is available, and zero otherwise.

Portability

The behavior and return value are platform-dependent.

Example

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/* system example : DIR */
#include <stdio.h>
#include <stdlib.h>

int main ()
{
  int i;
  printf ("Checking if processor is available...");
  if (system(NULL)) puts ("Ok");
    else exit (1);
  printf ("Executing command DIR...\n");
  i=system ("dir");
  printf ("The value returned was: %d.\n",i);
  return 0;
}


See also

exit Terminate calling process (function)