HP-UX Reference (11i v2 03/08) - 2 System Calls (vol 5)

getpid(2) getpid(2)

NAME

getpid(), getpgid(), getpgrp(), getpgrp2(), getppid() - get process, process group and parent process ID.

SYNOPSIS

#include <unistd.h>

pid_t getpgid (pid_t pid);

pid_t getpgrp(void);

pid_t getpgrp2(pid_t pid);

pid_t getpid(void);

pid_t getppid(void);

DESCRIPTION

These functions return process, process group and parent process IDs, as follows:

getpgid() Process group ID of the speciﬁed process. If pid is zero, the call applies to the

calling process. Same result as

getpgrp2().

getpgrp() Process group ID of the calling process.

getpgrp2() Process group ID of the speciﬁed process. If pid is zero, the call applies to the

calling process. Same result as

getpgid().

getpid() Process ID of the calling process.

getppid() Parent process ID of the calling process.

RETURN VALUE

The functions return the following values:

n Successful completion. n is a nonnegative process ID, as described above.

-1 Failure: getpgid() and getgrp2() only. errno is set to indicate the error.

ERRORS

getpgid() or getpgrp2() fails, errno is set to one of the following values:

[EPERM] The current process and pid are not in the same session (see setsid (2)).

[ESRCH] No process can be found corresponding to that speciﬁed by pid .

AUTHOR

getpid(), getppid(), getpgrp(), and getpgrp2() were developed by HP, AT&T, and the

University of California, Berkeley.