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Reference for unit 'Linux': Constants

Constant Description
CAP_AUDIT_CONTROL Allow manipulation of kernel auditing features
CAP_AUDIT_WRITE Allow writing to kernel audit log
CAP_CHOWN Perform chown operation
CAP_DAC_OVERRIDE Bypass file operation (rwx) checks
CAP_DAC_READ_SEARCH Bypass file read-only operation checks
CAP_FOWNER Bypass owner ID checks
CAP_FSETID Do not clear SUID/GUID bits on modified files
CAP_FS_MASK ?
CAP_IPC_LOCK Allow memory locking calls
CAP_IPC_OWNER Bypass permission checks on IPC operations
CAP_KILL Bypass permission checks for sending signals
CAP_LEASE Allow file leases
CAP_LINUX_IMMUTABLE Allow setting ext2 file attributes
CAP_MKNOD Allow creation of special files through mknod calls
CAP_NET_ADMIN Allow network operations (e.g. setting socket options)
CAP_NET_BIND_SERVICE Allow binding to ports less than 1024
CAP_NET_BROADCAST Allow socket broadcast operations
CAP_NET_RAW Allow use of RAW and PACKET sockets
CAP_SETGID Allow GID manipulations
CAP_SETPCAP Allow to set other process' capabilities
CAP_SETUID Allow process ID manipulations
CAP_SYS_ADMIN Allow various system administration calls
CAP_SYS_BOOT Allow reboot calls
CAP_SYS_CHROOT Allow chroot calls.
CAP_SYS_MODULE Allow loading/unloading of kernel modules
CAP_SYS_NICE Allowing raising process and thread priorities
CAP_SYS_PACCT Allow acct calls
CAP_SYS_PTRACE Allow ptrace calls
CAP_SYS_RAWIO Allow raw I/O port operations
CAP_SYS_RESOURCE Allow use of special resources or raising of resource limits
CAP_SYS_TIME Allow system or real-time clock modification
CAP_SYS_TTY_CONFIG Allow vhangup calls
CLOCKS_MASK Mask for supported clocks
CLOCKS_MONO Monotonic clocks mask
CLOCK_MONOTONIC Monotonic system time since some undetermined start point. Can change if time is set.
CLOCK_MONOTONIC_COARSE Less precise (but faster) version of CLOCK_MONOTONIC
CLOCK_MONOTONIC_RAW Like CLOCK_MONOTONIC, not subject to NTP adjustments
CLOCK_PROCESS_CPUTIME_ID Processs-specific high-resolution timer from the CPU.
CLOCK_REALTIME System wide real-time clock. Can only be set by root.
CLOCK_REALTIME_COARSE Less precise (but faster) version of CLOCK_REALTIME
CLOCK_SGI_CYCLE High resolution timer
CLOCK_THREAD_CPUTIME_ID Thread-specific high-resolution timer from the CPU.
CLONE_CHILD_CLEARTID Clone option: Erase child thread ID in child memory space when child exits.
CLONE_CHILD_SETTID Clone option: Store child thread ID in child memory.
CLONE_DETACHED Clone option: Start clone detached.
CLONE_FILES Clone option: open files shared between processes
CLONE_FS Clone option: fs info shared between processes
CLONE_NEWNS Clone options: Start child in new (file system) namespace.
CLONE_PARENT Clone options: Set child parent to parent of calling process.
CLONE_PARENT_SETTID Clone option: Store child thread ID in memory in both parent and child.
CLONE_PID Clone option: PID shared between processes
CLONE_PTRACE Clone options: if parent is traced, trace child also
CLONE_SETTLS Clone option: The newtls parameter is the TLS descriptor of the child
CLONE_SIGHAND Clone option: signal handlers shared between processes
CLONE_STOPPED Clone option: Start child in stopped state.
CLONE_SYSVSEM Clone option: Caller and child share the same semaphore undo values
CLONE_THREAD Clone options: Set child in thread group of calling process.
CLONE_UNTRACED Clone option: Do not allow a ptrace call on this clone.
CLONE_VFORK Clone options: suspend parent till child execs
CLONE_VM Clone option: VM shared between processes
CSIGNAL Clone option: Signal mask to be sent at exit
EPOLLERR event_wait error condition on file descriptor
EPOLLET Set event_wait edge trigger behaviour on file descriptor
EPOLLHUP event_wait hang up event
EPOLLIN event_wait input file descriptor ready event
EPOLLONESHOT Set single-shot behaviour on epoll_wait.
EPOLLOUT event_wait output file descriptor ready event
EPOLLPRI event_wait high priority data available on input file descriptor
EPOLL_CTL_ADD Add filedescriptor to list of events
EPOLL_CTL_DEL Delete event for filedescriptor
EPOLL_CTL_MOD Modify event for filedescriptor
FUTEX_CMP_REQUEUE Futex option: requeue waiting processes on other futex, but check it's value first
FUTEX_FD Futex option: Associate file descriptor with futex.
FUTEX_LOCK_PI Futex option: Undocumented
FUTEX_OP_ADD Futex operation: Undocumented
FUTEX_OP_ANDN Futex operation: Undocumented
FUTEX_OP_CMP_EQ Futex operation: Undocumented
FUTEX_OP_CMP_GE Futex operation: Undocumented
FUTEX_OP_CMP_GT Futex operation: Undocumented
FUTEX_OP_CMP_LE Futex operation: Undocumented
FUTEX_OP_CMP_LT Futex operation: Undocumented
FUTEX_OP_CMP_NE Futex operation: Undocumented
FUTEX_OP_OPARG_SHIFT Futex operation: Undocumented
FUTEX_OP_OR Futex operation: Undocumented
FUTEX_OP_SET Futex operation: Undocumented
FUTEX_OP_XOR Futex operation: Undocumented
FUTEX_REQUEUE Futex option: requeue waiting processes on other futex.
FUTEX_TRYLOCK_PI Futex option: Undocumented
FUTEX_UNLOCK_PI Futex option: Undocumented
FUTEX_WAIT Futex option: Wait on futex till wake call arrives.
FUTEX_WAKE Futex option: wakes any waiting processes on this futex
FUTEX_WAKE_OP Futex option: Undocumented
GIO_CMAP IOCTL: Get color palette on VGA+
GIO_FONT IOCTL: Get font in expanded form.
GIO_FONTX IOCTL: Get font in consolefontdesc record.
GIO_SCRNMAP IOCTL: get screen mapping from kernel
GIO_UNIMAP IOCTL: get unicode-to-font mapping from kernel
GIO_UNISCRNMAP IOCTL: get full Unicode screen mapping
IN_ACCESS Data was read from file.
IN_ALL_EVENTS All possible events OR-ed together.
IN_ATTRIB File attributes changed.
IN_CLOEXEC Inotify close on exec flag.
IN_CLOSE File was closed (read or write)
IN_CLOSE_NOWRITE File opened for read was closed
IN_CLOSE_WRITE File opened for write was closed
IN_CREATE A file was created in the directory.
IN_DELETE A file was deleted from the directory.
IN_DELETE_SELF Directory or file under observation was deleted.
IN_DONT_FOLLOW Do not follow symlinks
IN_IGNORED Watch was ignored (removed). Only reported.
IN_ISDIR Event subject is a directory (reported only)
IN_MASK_ADD Add events to existing watch (OR-ing the sets) if one exists.
IN_MODIFY Data was written to file.
IN_MOVE File was moved (in or out of directory)
IN_MOVED_FROM File was moved away from watched directory
IN_MOVED_TO File was moved into watched directory
IN_MOVE_SELF Directory or file under observation was moved.
IN_NONBLOCK Do not block on read
IN_ONESHOT Only report one event, then remove the watch.
IN_ONLYDIR Only watch filename if it is a directory.
IN_OPEN File was opened
IN_Q_OVERFLOW Queue overflowed. Only reported.
IN_UNMOUNT File system on which file resides was unmounted. Only reported.
KB_101 IOCTL: Keyboard types: 101 keys
KB_84 IOCTL: Keyboard types: 84 keys
KB_OTHER IOCTL: Keyboard types: other type
KDADDIO IOCTL: add i/o port as valid
KDDELIO IOCTL: delete i/o port as valid
KDDISABIO IOCTL: disable i/o to video board
KDENABIO IOCTL: enable i/o to video board
KDFONTOP IOCTL: font operations
KDGETKEYCODE IOCTL: read kernel keycode table entry
KDGETLED IOCTL: return current led state
KDGETMODE IOCTL: get current mode
KDGKBDIACR IOCTL: read kernel accent table
KDGKBTYPE IOCTL: get keyboard type
KDMAPDISP IOCTL: map display into address space
KDMKTONE IOCTL: generate tone
KDSETKEYCODE IOCTL: write kernel keycode table entry
KDSETLED IOCTL: set led state
KDSETMODE IOCTL: set text/graphics mode
KDSIGACCEPT IOCTL: accept kbd generated signals
KDSKBDIACR IOCTL: write kernel accent table
KDUNMAPDISP IOCTL: unmap display from address space
KD_GRAPHICS IOCTL: Tty modes: graphics mode
KD_TEXT IOCTL: Tty modes: Text mode
KD_TEXT0 IOCTL: Tty modes: Text mode (obsolete)
KD_TEXT1 IOCTL: Tty modes: Text mode (obsolete)
KIOCSOUND IOCTL: start/stop sound generation (0 for off)
LED_CAP IOCTL: LED_CAP : caps lock led
LED_NUM IOCTL: LED_SCR : Num lock led
LED_SCR IOCTL: LED_SCR : scroll lock led
LINUX_CAPABILITY_VERSION Current capability version in use by kernel
MAP_DENYWRITE Read-only
MAP_EXECUTABLE Memory area is marked as executable
MAP_GROWSDOWN Memory map grows down, like stack
MAP_LOCKED Memory pages are locked
MAP_NORESERVE Do not check for reservations
MAX_CLOCKS Maximum number of clocks in the system
MODIFY_LDT_CONTENTS_CODE Modify_ldt option: Undocumented
MODIFY_LDT_CONTENTS_DATA Modify_ldt option: Undocumented
MODIFY_LDT_CONTENTS_STACK Modify_ldt option: Undocumented
O_CLOEXEC Close on exec flag: close file handle on exec call
PIO_CMAP IOCTL: Set color palette on VGA+
PIO_FONT IOCTL: Use font in expanded form.
PIO_FONTRESET IOCTL: Reset to default font
PIO_FONTX IOCTL: Set font in consolefontdesc record.
PIO_SCRNMAP IOCTL: put screen mapping table in kernel
PIO_UNIMAP IOCTL: put unicode-to-font mapping in kernel
PIO_UNIMAPCLR IOCTL: clear table, possibly advise hash algorithm
PIO_UNISCRNMAP IOCTL: set full Unicode screen mapping
POLLMSG Unused in Linux
POLLRDHUP Peer Shutdown/closed writing half of connection
POLLREMOVE Undocumented Linux extension of Poll
SPLICE_F_GIFT Pages spliced in are a gift
SPLICE_F_MORE Expect more data
SPLICE_F_MOVE Move pages instead of copying
SPLICE_F_NONBLOCK Don't block on pipe splicing operations
STATX_ALL
STATX_ATIME
STATX_ATTR_APPEND
STATX_ATTR_AUTOMOUNT
STATX_ATTR_COMPRESSED
STATX_ATTR_ENCRYPTED
STATX_ATTR_IMMUTABLE
STATX_ATTR_NODUMP
STATX_BASIC_STATS
STATX_BLOCKS
STATX_BTIME
STATX_CTIME
STATX_GID
STATX_INO
STATX_MODE
STATX_MTIME
STATX_NLINK
STATX_SIZE
STATX_TYPE
STATX_UID
STATX__RESERVED
SYNC_FILE_RANGE_WAIT_AFTER Wait upon write-out of specified pages in the range after performing any write.
SYNC_FILE_RANGE_WAIT_BEFORE Wait for write-out of previously-submitted specified pages before writing more data.
SYNC_FILE_RANGE_WRITE Initiate write of all dirty pages in the specified range.
UD_CONTENTS_CODE TLS segment descriptor: Undocumented
UD_CONTENTS_DATA TLS segment descriptor: Undocumented
UD_CONTENTS_STACK TLS segment descriptor: Undocumented
UD_LIMIT_IN_PAGES TLS segment descriptor: Undocumented
UD_LM TLS segment descriptor: Undocumented
UD_READ_EXEC_ONLY TLS segment descriptor: Undocumented
UD_SEG_32BIT TLS segment descriptor : Undocumented
UD_SEG_NOT_PRESENT TLS segment descriptor: Undocumented
UD_USEABLE TLS segment descriptor: Undocumented