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 shmctl – System V shared memory control SYNOPSIS #include <sys/ipc.h> #include <sys/shm.h> int shmctl(int shmid, int cmd, struct shmid_ds *buf); DESCRIPTION shmctl() performs the control operation specified by cmd on the System V shared memory segment whose identifier is given in shmid. The buf argument is a pointer to a shmid_ds structure, defined in…
NAME shmat, shmdt – System V shared memory operations SYNOPSIS #include <sys/shm.h> #include <sys/types.h> void *shmat(int shmid, const void *shmaddr, int shmflg); int shmdt(const void *shmaddr); DESCRIPTION shmat() shmat() attaches the System V shared memory segment identified by shmid to the address space of the calling process. The attaching address is specified by shmaddr with…
NAME sgetmask, ssetmask – manipulation of signal mask (obsolete) SYNOPSIS long sgetmask(void); long ssetmask(long newmask); Note: There are no glibc wrappers for these system calls; see NOTES. DESCRIPTION These system calls are obsolete. Do not use them; use sigprocmask(2) instead. sgetmask() returns the signal mask of the calling process. ssetmask() sets the signal mask of…
NAME setxattr, lsetxattr, fsetxattr – set an extended attribute value SYNOPSIS #include <sys/types.h> #include <sys/xattr.h> int setxattr(const char *path, const char *name, const void *value, size_t size, int flags); int lsetxattr(const char *path, const char *name, const void *value, size_t size, int flags); int fsetxattr(int fd, const char …
NAME setup – setup devices and filesystems, mount root filesystem SYNOPSIS #include <unistd.h> int setup(void); DESCRIPTION setup() is called once from within linux/init/main.c. It calls initialization functions for devices and filesystems configured into the kernel and then mounts the root filesystem. No user process may call setup(). Any user process, even a process with superuser…
NAME setuid – set user identity SYNOPSIS #include <sys/types.h> #include <unistd.h> int setuid(uid_t uid); DESCRIPTION setuid() sets the effective user ID of the calling process. If the calling process is privileged (more precisely: if the process has the CAP_SETUID capability in its user namespace), the real UID and saved set-user-ID are also set. Under Linux,…
NAME setuid – set user identity SYNOPSIS #include <sys/types.h> #include <unistd.h> int setuid(uid_t uid); DESCRIPTION setuid() sets the effective user ID of the calling process. If the calling process is privileged (more precisely: if the process has the CAP_SETUID capability in its user namespace), the real UID and saved set-user-ID are also set. Under Linux,…
NAME gettimeofday, settimeofday – get / set time SYNOPSIS #include <sys/time.h> int gettimeofday(struct timeval *tv, struct timezone *tz); int settimeofday(const struct timeval *tv, const struct timezone *tz); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): settimeofday(): Since glibc 2.19: _DEFAULT_SOURCE Glibc 2.19 and earlier: _BSD_SOURCE DESCRIPTION The functions gettimeofday() and settimeofday() can get and set…
NAME getsockopt, setsockopt – get and set options on sockets SYNOPSIS #include <sys/socket.h> #include <sys/types.h> /* See NOTES */ int getsockopt(int sockfd, int level, int optname, void *optval, socklen_t *optlen); int setsockopt(int sockfd, int level, int optname, const void *optval, socklen_t optlen); DESCRIPTION getsockopt() and setsockopt() manipulate options for the socket referred to by the…
NAME setsid – creates a session and sets the process group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> pid_t setsid(void); DESCRIPTION setsid() creates a new session if the calling process is not a process group leader. The calling process is the leader of the new session (i.e., its session ID is made the same as its…
NAME getrlimit, setrlimit, prlimit – get/set resource limits SYNOPSIS #include <sys/time.h> #include <sys/resource.h> int getrlimit(int resource, struct rlimit *rlim); int setrlimit(int resource, const struct rlimit *rlim); int prlimit(pid_t pid, int resource, const struct rlimit *new_limit, struct rlimit *old_limit); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): prlimit(): _GNU_SOURCE DESCRIPTION The getrlimit() and setrlimit() system calls…
NAME setreuid, setregid – set real and/or effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int setreuid(uid_t ruid, uid_t euid); int setregid(gid_t rgid, gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setreuid(), setregid(): _XOPEN_SOURCE >= 500 || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION setreuid() sets real and effective user IDs of the calling process….
NAME setreuid, setregid – set real and/or effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int setreuid(uid_t ruid, uid_t euid); int setregid(gid_t rgid, gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setreuid(), setregid(): _XOPEN_SOURCE >= 500 || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION setreuid() sets real and effective user IDs of the calling process….
NAME setresuid, setresgid – set real, effective and saved user or group ID SYNOPSIS #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <unistd.h> int setresuid(uid_t ruid, uid_t euid, uid_t suid); int setresgid(gid_t rgid, gid_t egid, gid_t sgid); DESCRIPTION setresuid() sets the real user ID, the effective user ID, and the saved set-user-ID of the calling process….
NAME setresuid, setresgid – set real, effective and saved user or group ID SYNOPSIS #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <unistd.h> int setresuid(uid_t ruid, uid_t euid, uid_t suid); int setresgid(gid_t rgid, gid_t egid, gid_t sgid); DESCRIPTION setresuid() sets the real user ID, the effective user ID, and the saved set-user-ID of the calling process….
NAME setresuid, setresgid – set real, effective and saved user or group ID SYNOPSIS #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <unistd.h> int setresuid(uid_t ruid, uid_t euid, uid_t suid); int setresgid(gid_t rgid, gid_t egid, gid_t sgid); DESCRIPTION setresuid() sets the real user ID, the effective user ID, and the saved set-user-ID of the calling process….
NAME setresuid, setresgid – set real, effective and saved user or group ID SYNOPSIS #define _GNU_SOURCE /* See feature_test_macros(7) */ #include <unistd.h> int setresuid(uid_t ruid, uid_t euid, uid_t suid); int setresgid(gid_t rgid, gid_t egid, gid_t sgid); DESCRIPTION setresuid() sets the real user ID, the effective user ID, and the saved set-user-ID of the calling process….
NAME setreuid, setregid – set real and/or effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int setreuid(uid_t ruid, uid_t euid); int setregid(gid_t rgid, gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setreuid(), setregid(): _XOPEN_SOURCE >= 500 || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION setreuid() sets real and effective user IDs of the calling process….
NAME setreuid, setregid – set real and/or effective user or group ID SYNOPSIS #include <sys/types.h> #include <unistd.h> int setreuid(uid_t ruid, uid_t euid); int setregid(gid_t rgid, gid_t egid); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): setreuid(), setregid(): _XOPEN_SOURCE >= 500 || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE DESCRIPTION setreuid() sets real and effective user IDs of the calling process….
NAME getpriority, setpriority – get/set program scheduling priority SYNOPSIS #include <sys/time.h> #include <sys/resource.h> int getpriority(int which, id_t who); int setpriority(int which, id_t who, int prio); DESCRIPTION The scheduling priority of the process, process group, or user, as indicated by which and who is obtained with the getpriority() call and set with the setpriority() call. The…