getpid(2) System Calls Manual getpid(2) getpid getppid - (libc -lc) #include pid_t getpid(void); pid_t getppid(void); getpid() (PID) . ( .) getppid() . fork() ( init(1) "subreaper" PR_SET_CHILD_SUBREAPER prctl(2)). . Alpha getpid() getppid() getxpid() PID . getpid() getppid() glibc . syscall(2) . POSIX.1-2024. 4.3BSD SVr4 POSIX.1-1988. C 2.3.4 glibc 2.24 ( ) glibc getpid() PIDs getpid() . fork(2) vfork(2) clone(2): glibc syscall(2) getpid() ( : PID ). getpid() clone(2) glibc. ( BUGS clone(2).) glibc . PID 2.25 glibc: getpid() . PID ( pid_namespaces(7)) getppid() 0. PID ( ) (TGID). (TID) . gettid(2) CLONE_THREAD clone(2). clone(2), fork(2), gettid(2), kill(2), exec(3), mkstemp(3), tempnam(3), tmpfile(3), tmpnam(3), credentials(7), pid_namespaces(7) 3 . . : . 6.18 8 2026 getpid(2)