The Linux Manuals (man pages) document is an important part of Linux documents. Linux Manuals are organized as several sections. Each section has a group of commands for a specific area in Linux usage, administration or development.
NAME setpgid, getpgid, setpgrp, getpgrp – set/get process group SYNOPSIS #include <sys/types.h> #include <unistd.h> int setpgid(pid_t pid, pid_t pgid); pid_t getpgid(pid_t pid); pid_t getpgrp(void); /* POSIX.1 version */ pid_t getpgrp(pid_t pid); /* BSD version */ int setpgrp(void); /* System V version */ int setpgrp(pid_t pid, pid_t pgid); /* BSD version */ Feature Test Macro Requirements…
NAME setpgid, getpgid, setpgrp, getpgrp – set/get process group SYNOPSIS #include <sys/types.h> #include <unistd.h> int setpgid(pid_t pid, pid_t pgid); pid_t getpgid(pid_t pid); pid_t getpgrp(void); /* POSIX.1 version */ pid_t getpgrp(pid_t pid); /* BSD version */ int setpgrp(void); /* System V version */ int setpgrp(pid_t pid, pid_t pgid); /* BSD version */ Feature Test Macro Requirements…
NAME setns – reassociate thread with a namespace SYNOPSIS #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <sched.h> int setns(int fd, int nstype); DESCRIPTION The setns() system call allows the calling thread to move into different namespaces. The fd argument is one of the following: • a file descriptor referring to one of the magic links…
NAME getitimer, setitimer – get or set value of an interval timer SYNOPSIS #include <sys/time.h> int getitimer(int which, struct itimerval *curr_value); int setitimer(int which, const struct itimerval *new_value, struct itimerval *old_value); DESCRIPTION These system calls provide access to interval timers, that is, timers that initially expire at some point in the future, and (optionally) at…
NAME gethostname, sethostname – get/set hostname SYNOPSIS #include <unistd.h> int gethostname(char *name, size_t len); int sethostname(const char *name, size_t len); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): gethostname(): Since glibc 2.12: _BSD_SOURCE || _XOPEN_SOURCE >= 500 || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200112L sethostname(): Since glibc 2.21 : _DEFAULT_SOURCE In glibc 2.19 and 2.20 : _DEFAULT_SOURCE…
NAME gethostid, sethostid – get or set the unique identifier of the current host SYNOPSIS #include <unistd.h> long gethostid(void); int sethostid(long hostid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): gethostid(): _BSD_SOURCE || _XOPEN_SOURCE >= 500 sethostid(): Since glibc 2.21 : _DEFAULT_SOURCE In glibc 2.19 and 2.20 : _DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE & nbsp; < …
NAME getgroups, setgroups – get/set list of supplementary group IDs SYNOPSIS #include <sys/types.h> #include <unistd.h> int getgroups(int size, gid_t list[]); #include <grp.h> int setgroups(size_t size, const gid_t *list); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setgroups(): Since glibc 2.19: _DEFAULT_SOURCE Glibc 2.19 and earlier: _BSD_SOURCE DESCRIPTION getgroups() returns the supplementary group IDs of the…
NAME getgroups, setgroups – get/set list of supplementary group IDs SYNOPSIS #include <sys/types.h> #include <unistd.h> int getgroups(int size, gid_t list[]); #include <grp.h> int setgroups(size_t size, const gid_t *list); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setgroups(): Since glibc 2.19: _DEFAULT_SOURCE Glibc 2.19 and earlier: _BSD_SOURCE DESCRIPTION getgroups() returns the supplementary group IDs of the…
NAME setgid – set group identity SYNOPSIS #include <sys/types.h> #include <unistd.h> int setgid(gid_t gid); DESCRIPTION setgid() sets the effective group ID of the calling process. If the calling process is privileged (more precisely: has the CAP_SETGID capability in its user namespace), the real GID and saved set-group-ID are also set. Under Linux, setgid() is implemented…
NAME setgid – set group identity SYNOPSIS #include <sys/types.h> #include <unistd.h> int setgid(gid_t gid); DESCRIPTION setgid() sets the effective group ID of the calling process. If the calling process is privileged (more precisely: has the CAP_SETGID capability in its user namespace), the real GID and saved set-group-ID are also set. Under Linux, setgid() is implemented…
NAME setfsuid – set user identity used for filesystem checks SYNOPSIS #include <sys/fsuid.h> int setfsuid(uid_t fsuid); DESCRIPTION On Linux, a process has both a filesystem user ID and an effective user ID. The (Linux-specific) filesystem user ID is used for permissions checking when accessing filesystem objects, while the effective user ID is used for various…
NAME setfsuid – set user identity used for filesystem checks SYNOPSIS #include <sys/fsuid.h> int setfsuid(uid_t fsuid); DESCRIPTION On Linux, a process has both a filesystem user ID and an effective user ID. The (Linux-specific) filesystem user ID is used for permissions checking when accessing filesystem objects, while the effective user ID is used for various…
NAME setfsgid – set group identity used for filesystem checks SYNOPSIS #include <sys/fsuid.h> int setfsgid(uid_t fsgid); DESCRIPTION On Linux, a process has both a filesystem group ID and an effective group ID. The (Linux-specific) filesystem group ID is used for permissions checking when accessing filesystem objects, while the effective group ID is used for some…
NAME setfsgid – set group identity used for filesystem checks SYNOPSIS #include <sys/fsuid.h> int setfsgid(uid_t fsgid); DESCRIPTION On Linux, a process has both a filesystem group ID and an effective group ID. The (Linux-specific) filesystem group ID is used for permissions checking when accessing filesystem objects, while the effective group ID is used for some…
NAME seteuid, setegid – set effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int seteuid(uid_t euid); int setegid(gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): seteuid(), setegid(): _POSIX_C_SOURCE >= 200112L || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION seteuid() sets the effective user ID of the calling process. Unprivileged processes may only set the effective user ID to…
NAME seteuid, setegid – set effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int seteuid(uid_t euid); int setegid(gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): seteuid(), setegid(): _POSIX_C_SOURCE >= 200112L || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION seteuid() sets the effective user ID of the calling process. Unprivileged processes may only set the effective user ID to…
NAME getdomainname, setdomainname – get/set NIS domain name SYNOPSIS #include <unistd.h> int getdomainname(char *name, size_t len); int setdomainname(const char *name, size_t len); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): getdomainname(), setdomainname(): Since glibc 2.21 : _DEFAULT_SOURCE In glibc 2.19 and 2.20 : _DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE & nbsp; < 500) Up to…
NAME getcontext, setcontext – get or set the user context SYNOPSIS #include <ucontext.h> int getcontext(ucontext_t *ucp); int setcontext(const ucontext_t *ucp); DESCRIPTION In a System V-like environment, one has the two types mcontext_t and ucontext_t defined in <ucontext.h> and the four functions getcontext(), setcontext(), makecontext(3), and swapcontext(3) that allow user-level context switching between multiple threads of…
NAME set_tid_address – set pointer to thread ID SYNOPSIS #include <linux/unistd.h> pid_t set_tid_address(int *tidptr); Note: There is no glibc wrapper for this system call; see NOTES. DESCRIPTION For each thread, the kernel maintains two attributes (addresses) called set_child_tid and clear_child_tid. These two attributes contain the value NULL by default. set_child_tid If a thread is started…
NAME get_thread_area, set_thread_area – manipulate thread-local storage information SYNOPSIS #include <linux/unistd.h> #if defined __i386__ || defined __x86_64__ #include <asm/ldt.h> int get_thread_area(struct user_desc *u_info); int set_thread_area(struct user_desc *u_info); #elif defined __m68k__ int get_thread_area(void); int set_thread_area(unsigned long tp); #elif defined __mips__ int set_thread_area(unsigned long addr); #endif Note: There are no glibc wrappers for these system calls; see…