SYSTEM(CMD, RESULT) (IBM extension)

Purpose

Passes a command to the operating system for execution. The current process pauses until the command is completed and control is returned from the operating system. An added, optional argument to the subroutine will allow recovery of any return code information from the operating system.

Class

Subroutine

Argument type and attributes

CMD: An INTENT(IN) CHARACTER scalar. It specifies the command to execute and any command-line arguments.
RESULT (optional): An INTENT(OUT) INTEGER(4) scalar. If the argument is not an INTEGER(4) variable, the compiler generates an (S) level error message. The format of the information returned in RESULT is the same as the format returned from the wait system call.

Examples

      INTEGER        ULIMIT
      CHARACTER(32)  CMD
      …
! Check the system ulimit.
      CMD = 'ulimit > ./fort.99'
      CALL SYSTEM(CMD)
      READ(99, *) ULIMIT
      IF (ULIMIT .LT. 2097151) THEN
         …

     INTEGER RC
     RC=99
     CALL SYSTEM("/bin/test 1 -EQ 2",RC)
     IF (IAND(RC,'ff'z) .EQ. 0) then
       RC = IAND( ISHFT(RC,-8), 'ff'z )
     ELSE
       RC = -1
     ENDIF

Related information

EXECUTE_COMMAND_LINE(COMMAND, WAIT, EXITSTAT, CMDSTAT, CMDMSG) (Fortran 2008)

See the system subroutine in the AIX® Technical Reference: Base Operating System and Extensions Volume 2 for details about the underlying implementation.