PXFFORK (L*X, M*X)

POSIX Subroutine: Creates a child process that differs from the parent process only in its PID.

Module: USE IFPOSIX

Syntax

CALL PXFFORK (ipid, ierror)

ipid
(Output) INTEGER(4). The returned PID of the new child process.

ierror
(Output) INTEGER(4). The error status.

If successful, ierror is set to zero; otherwise, an error code.

The PXFFORK subroutine creates a child process that differs from the parent process only in its PID. If successful, the PID of the child process is returned in the parent's thread of execution, and a zero is returned in the child's thread of execution. Otherwise, a -1 is returned in the parent's context and no child process is created.

See Also

IPXWEXITSTATUS

Example

program t1  
use ifposix  
integer(4) ipid, istat, ierror, ipid_ret, istat_ret  
  print *," the child process will be born"
  call PXFFORK(IPID, IERROR)
  call PXFGETPID(IPID_RET,IERROR)  
  if(IPID.EQ.0) then
     print *," I am a child process"
     print *," My child's pid is", IPID_RET
     call PXFGETPPID(IPID_RET,IERROR)
     print *," The pid of my parent is",IPID_RET
     print *," Now I have exited with code 0xABCD"
     call PXFEXIT(Z'ABCD')
  else
     print *," I am a parent process"
     print *," My parent pid is ", IPID_RET
     print *," I am creating the process with pid", IPID
     print *," Now I am waiting for the end of the child process"
     call PXFWAIT(ISTAT, IPID_RET, IERROR)
     print *," The child with pid ", IPID_RET," has exited"
     if( PXFWIFEXITED(ISTAT) ) then
       print *, " The child exited normally"
       istat_ret = IPXFWEXITSTATUS(ISTAT)
       print 10," The low byte of the child exit code is", istat_ret
     end if   
  end if
10 FORMAT (A,Z)  
end program