pid_t3type
Process/user/group identifier
Part of id_t(3type).
Usage
typedef /* ...
*/
pid_t;
typedef
/* ...
*/
uid_t;
typedef
/* ...
*/
gid_t;
typedef
/* ...
*/
id_t;
Library
Standard C library (libc)
Overview
pid_t is a type used for storing process IDs, process group IDs, and session IDs. It is a signed integer type.
uid_t is a type used to hold user IDs. It is an integer type.
gid_t is a type used to hold group IDs. It is an integer type.
id_t is a type used to hold a general identifier. It is an integer type that can be used to contain a pid_t, uid_t, or gid_t.
Notes
The following headers also provide pid_t: <fcntl.h>, <sched.h>, <signal.h>, <spawn.h>, <sys/msg.h>, <sys/sem.h>, <sys/shm.h>, <sys/wait.h>, <termios.h>, <time.h>, <unistd.h>, and <utmpx.h>.
The following headers also provide uid_t: <pwd.h>, <signal.h>, <stropts.h>, <sys/ipc.h>, <sys/stat.h>, and <unistd.h>.
The following headers also provide gid_t: <grp.h>, <pwd.h>, <signal.h>, <stropts.h>, <sys/ipc.h>, <sys/stat.h>, and <unistd.h>.
The following header also provides id_t: <sys/resource.h>.
History
- Arch Linux 2026-11-01: the text shown here
- Debian 13 (Trixie)
- Debian 12 (Bookworm)