setpgid(2)                          CLIX                          setpgid(2)



  NAME

    setpgid - Sets the process group ID

  SYNOPSIS

    #include <sys/types.h>

    int setpgid(
      pid_t process_id ,
      pid_t process_group_id );

  PARAMETERS

    process_id
           Specifies the process for which the process group ID is to be
           changed.

    process_group_id
           Specifies the new process group ID.

  DESCRIPTION

    The setpgid() function is used either to join an existing process group or
    to create a new process group within the session of the calling process.
    The process group ID of a session leader will not change.

    The process group ID of the process designated by process_id is set to the
    value of the process_group_id parameter.  If either process_id or
    process_group_id is 0, the process ID or process group ID of the calling
    process is used.

    This function is implemented to support job control.

  RETURN VALUES

    Upon successful completion a value of 0 is returned.  Otherwise, a value
    of -1 is returned and errno is set to indicate the error.

  ERRORS

    When the setpgid() function fails, the following error statuses are
    returned:

    [EINVAL]   The value of the process_group_id parameter is less than or
               equal to 0, or is not a valid process ID.

    [EPERM]    The process indicated by pid is a session leader.

               The value of pid is valid but matches the process ID of a child
               process of the calling process and the child process is not in



  2/94 - Intergraph Corporation                                              1

  setpgid(2)                          CLIX                          setpgid(2)



               the same session as the calling process.

               The value of pgid does not match the process ID of the process
               indicated by pid and there is no process with a process group
               ID that matches the value of pgid in the same session as the
               calling process.

    [ESRCH]    The value of process_id does not match the process ID of the
               calling process or of a child process of the calling process.

    [EACCES]   The value of process_id matches the process ID of a child
               process of the calling process and the child process has
               successfully executed one of the exec() functions.

  RELATED INFORMATION

    Functions:  getpid(2), setsid(2), setpgrp(2)





































  2                                              Intergraph Corporation - 2/94