pxfsetsid

Date:: 10-20-2011

NAME

PXFSETSID - Creates a new session for a calling process

SYNOPSIS

INTEGER isid, ierror
CALL PXFSETSID(isid, ierror)

IMPLEMENTATION

Cray Linux Environment (CLE)

DESCRIPTION

The PXFSETSID routine uses the setsid(2) system call to create a new session for the calling process. The calling process must not be the process leader for PXFSETSID to be successful.

After the successful completion of PXFSETSID, the calling process will be the session leader for the new session and the process group leader for the new process group. The calling process also will have no controlling terminal.

All arguments must be of default kind unless documented otherwise. Default kind is KIND=4 for integer, real, complex, and logical arguments.

The following is a list of arguments for this routine:

isid: An output integer variable for the new process group ID of the calling process.
ierror: An output integer variable that contains zero if PXFSETSID was successful or nonzero if PXFSETSID was not successful.

This routine may return the EPERM error value if the calling process is already a process group leader, or the calling process group ID of a process other than the calling process matches the process ID of the calling process.

EXAMPLES

In this example, PXFFORK is called to create a child process, which calls PXFSETSID to create a new session. The child writes the value of ierror to Fortran unit 10 and stops. After the fork, the parent process waits for the child to finish execution, and then reads from Fortran unit 10. If the value read in from unit 10 is not equal to zero, the child’s call to PXFSETSID was unsucessful.

program pxftest
integer isid, iretpid, istat, ierror, i

CALL PXFFORK(iretpid,ierror)
if (ierror .ne. 0) then
   print *,'FAILED: PXFFORK call with error = ',ierror
else
   if (iretpid .eq. 0) then
      CALL PXFSETSID(isid, ierror)
      write (10,*) ierror
      stop
   else
      CALL PXFWAIT(istat, iretpid, ierror)
      read (10,*) i
      if (i .eq. 0) then
         print *,'PASSED: PXFSETSID call under normal conditions'
      else
         print *,'FAILED: PXFSETSID call with error = ',i
      endif
   endif
endif