getsid - get session ID
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
returns the session ID of the calling process. getsid
returns the session ID of the process with process ID pid
is 0, getsid
() returns the session ID of the calling
On success, a session ID is returned. On error, (pid_t) -1
returned, and errno
is set appropriately.
- A process with process ID pid 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 pid was found.
This system call is available on Linux since version 2.0.
POSIX.1-2001, POSIX.1-2008, SVr4.
Linux does not return EPERM
for a description of sessions and session IDs.
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