pid_t getsid(pid_t pid);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_XOPEN_SOURCE >= 500
|| /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L
DESCRIPTIONgetsid(0) returns the session ID of the calling process. getsid(p) returns the session ID of the process with process ID p. (The session ID of a process is the process group ID of the session leader.)
RETURN VALUEOn success, a session ID is returned. On error, (pid_t) -1 will be returned, and errno is set appropriately.
- A process with process ID p exists, but it is not in the same session as the calling process, and the implementation considers this an error.
- No process with process ID p was found.
VERSIONSThis system call is available on Linux since version 2.0.
CONFORMING TOPOSIX.1-2001, POSIX.1-2008, SVr4.
NOTESLinux does not return EPERM.
COLOPHONThis page is part of release 4.06 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.