getsid(2)

NAME

     getsid - get process group ID of session leader

SYNOPSIS

     #include <unistd.h>

     pid_t getsid(pid_t pid);

DESCRIPTION

     The getsid() function obtains the process group  ID  of  the
     process  that is the session leader of the process specified
     by pid.
      If pid is (pid_t)0, it specifies the calling process.

RETURN VALUES

     Upon successful completion,  getsid()  returns  the  process
     group  ID  of  the  session leader of the specified process.
     Otherwise, it returns (pid_t)-1 and sets errno  to  indicate
     the error.

ERRORS

     The getsid() function will fail if:

     EPERM The process specified by pid is not in the  same  ses-
           sion  as  the  calling process, and the implementation
           does not allow access to the process group ID  of  the
           session  leader  of that process from the calling pro-
           cess.

     ESRCH There is no process with a process ID equal to pid.

SEE ALSO

     exec(2), fork(2), getpid(2),  getpgid(2),  setpgid(2),  set-
     sid(2)