Module `syscall`

Accessing kernel system call information.

This library allows retrieving the kernel address of a system call given its number, and provides a table of system call numbers accessible by their names (see syscall.numbers). This is particularly useful for kernel probing (see probe) or other low-level kernel interactions.

syscall

address (syscall_number)	Retrieves the kernel address of a system call.
numbers	Table of system call numbers.

syscall

address (syscall_number)

Retrieves the kernel address of a system call.

Parameters:

syscall_number integer The system call number (e.g., __NR_openat).

Returns:

lightuserdata

nil

Raises:

Error if syscall_number is out of bounds.

Usage:

local syscall = require("syscall")
local openat_addr = syscall.address(syscall.numbers.openat)

numbers

Table of system call numbers. This table maps system call names (strings) to their corresponding kernel system call numbers (integers, e.g., __NR_openat). The availability of specific system calls depends on the kernel version and architecture, as detailed below.

Fields:

io_setup integer Create an asynchronous I/O context.
io_destroy integer Destroy an asynchronous I/O context.
io_submit integer Submit asynchronous I/O blocks.
io_cancel integer Cancel an outstanding asynchronous I/O operation.
setxattr integer Set an extended attribute value.
lsetxattr integer Set an extended attribute value of a symbolic link.
fsetxattr integer Set an extended attribute value of an open file.
getxattr integer Get an extended attribute value.
lgetxattr integer Get an extended attribute value of a symbolic link.
fgetxattr integer Get an extended attribute value of an open file.
listxattr integer List extended attribute names.
llistxattr integer List extended attribute names of a symbolic link.
flistxattr integer List extended attribute names of an open file.
removexattr integer Remove an extended attribute.
lremovexattr integer Remove an extended attribute of a symbolic link.
fremovexattr integer Remove an extended attribute of an open file.
getcwd integer Get current working directory.
lookup_dcookie integer Return a directory entry's path.
eventfd2 integer Create a file descriptor for event notification.
epoll_create1 integer Open an epoll file descriptor.
epoll_ctl integer Control interface for an epoll file descriptor.
epoll_pwait integer Wait for an I/O event on an epoll file descriptor.
dup integer Duplicate an old file descriptor.
dup3 integer Duplicate an old file descriptor to a new one with flags.
inotify_init1 integer Initialize an inotify instance.
inotify_add_watch integer Add a watch to an initialized inotify instance.
inotify_rm_watch integer Remove an existing watch from an inotify instance.
ioctl integer Control a device.
ioprio_set integer Set I/O scheduling class and priority.
ioprio_get integer Get I/O scheduling class and priority.
flock integer Apply or remove an advisory lock on an open file.
mknodat integer Create a special or ordinary file relative to a directory file descriptor.
mkdirat integer Create a directory relative to a directory file descriptor.
unlinkat integer Remove a file relative to a directory file descriptor.
symlinkat integer Create a symbolic link relative to a directory file descriptor.
linkat integer Make a new name for a file relative to a directory file descriptor.
umount2 integer Unmount a filesystem with flags.
mount integer Mount a filesystem.
pivot_root integer Change the root filesystem.
nfsservctl integer Syscall for NFS server control (obsolete).
fallocate integer Manipulate file space.
faccessat integer Check user's permissions for a file relative to a directory file descriptor.
chdir integer Change working directory.
fchdir integer Change working directory using a file descriptor.
chroot integer Change root directory.
fchmod integer Change permissions of a file given a file descriptor.
fchmodat integer Change permissions of a file relative to a directory file descriptor.
fchownat integer Change ownership of a file relative to a directory file descriptor.
fchown integer Change ownership of a file given a file descriptor.
openat integer Open or create a file relative to a directory file descriptor.
close integer Close a file descriptor.
vhangup integer Virtually hangup the current tty.
pipe2 integer Create a pipe with flags.
quotactl integer Manipulate disk quotas.
getdents64 integer Get directory entries.
read integer Read from a file descriptor.
write integer Write to a file descriptor.
readv integer Read data into multiple buffers.
writev integer Write data from multiple buffers.
pread64 integer Read from a file descriptor at a given offset.
pwrite64 integer Write to a file descriptor at a given offset.
preadv integer Read data into multiple buffers from a given offset.
pwritev integer Write data from multiple buffers at a given offset.
signalfd4 integer Create a file descriptor for accepting signals.
vmsplice integer Splice user pages to a pipe.
splice integer Splice data to/from a pipe.
tee integer Duplicate pipe content.
readlinkat integer Read value of a symbolic link relative to a directory file descriptor.
sync integer Commit filesystem caches to disk.
fsync integer Synchronize a file's in-core state with storage device.
fdatasync integer Synchronize a file's data in-core state with storage device.
timerfd_create integer Create a file descriptor for timer notifications.
acct integer Switch process accounting on or off.
capget integer Get process capabilities.
capset integer Set process capabilities.
personality integer Set the process execution domain.
exit integer Terminate the current process.
exit_group integer Terminate all threads in a process.
waitid integer Wait for process state changes.
set_tid_address integer Set pointer to thread ID.
unshare integer Disassociate parts of the process execution context.
set_robust_list integer Set the address of the robust futex list.
get_robust_list integer Get the address of the robust futex list.
getitimer integer Get value of an interval timer.
setitimer integer Set value of an interval timer.
kexec_load integer Load a new kernel for later execution.
init_module integer Load a kernel module.
delete_module integer Unload a kernel module.
timer_create integer Create a POSIX per-process timer.
timer_getoverrun integer Get POSIX per-process timer overrun count.
timer_delete integer Delete a POSIX per-process timer.
syslog integer Read and/or clear kernel message ring buffer; set console_loglevel.
ptrace integer Process trace.
sched_setparam integer Set scheduling parameters for a process.
sched_setscheduler integer Set scheduling policy and parameters for a process.
sched_getscheduler integer Get scheduling policy for a process.
sched_getparam integer Get scheduling parameters for a process.
sched_setaffinity integer Set a thread's CPU affinity mask.
sched_getaffinity integer Get a thread's CPU affinity mask.
sched_yield integer Yield the processor.
sched_get_priority_max integer Get maximum priority value for a scheduling policy.
sched_get_priority_min integer Get minimum priority value for a scheduling policy.
sched_rr_get_interval integer Get the SCHED_RR interval for the named process.
restart_syscall integer Restart a system call after a signal.
kill integer Send signal to a process.
tkill integer Send signal to a thread.
tgkill integer Send signal to a thread group.
sigaltstack integer Set and/or get signal stack context.
rt_sigsuspend integer Wait for a real-time signal.
rt_sigaction integer Examine and change a real-time signal action.
rt_sigprocmask integer Examine and change blocked real-time signals.
rt_sigpending integer Examine pending real-time signals.
rt_sigqueueinfo integer Queue a real-time signal and data.
rt_sigreturn integer Return from signal handler and cleanup stack frame.
setpriority integer Set program scheduling priority.
getpriority integer Get program scheduling priority.
reboot integer Reboot or enable/disable Ctrl-Alt-Del.
setregid integer Set real and effective group IDs.
setgid integer Set effective group ID.
setreuid integer Set real and effective user IDs.
setuid integer Set effective user ID.
setresuid integer Set real, effective and saved user IDs.
getresuid integer Get real, effective and saved user IDs.
setresgid integer Set real, effective and saved group IDs.
getresgid integer Get real, effective and saved group IDs.
setfsuid integer Set filesystem user ID.
setfsgid integer Set filesystem group ID.
times integer Get process times.
setpgid integer Set process group ID.
getpgid integer Get process group ID.
getsid integer Get session ID.
setsid integer Create a session and set the process group ID.
getgroups integer Get list of supplementary group IDs.
setgroups integer Set list of supplementary group IDs.
uname integer Get name and information about current kernel.
sethostname integer Set the system's hostname.
setdomainname integer Set the system's NIS/YP domain name.
getrusage integer Get resource usage.
umask integer Set file mode creation mask.
prctl integer Operations on a process or thread.
getcpu integer Determine CPU and NUMA node on which the calling thread is running.
getpid integer Get process ID.
getppid integer Get parent process ID.
getuid integer Get real user ID.
geteuid integer Get effective user ID.
getgid integer Get real group ID.
getegid integer Get effective group ID.
gettid integer Get thread ID.
sysinfo integer Get system information.
mq_open integer Open a POSIX message queue.
mq_unlink integer Unlink a POSIX message queue.
mq_timedsend integer Send a message to a POSIX message queue with timeout.
mq_timedreceive integer Receive a message from a POSIX message queue with timeout.
mq_notify integer Register for asynchronous notification of message arrival on a POSIX message queue.
mq_getsetattr integer Get/set POSIX message queue attributes.
msgget integer Get a System V message queue identifier.
msgctl integer System V message control operations.
msgrcv integer Receive messages from a System V message queue.
msgsnd integer Send a message to a System V message queue.
semget integer Get a System V semaphore set identifier.
semctl integer System V semaphore control operations.
semop integer System V semaphore operations.
shmget integer Allocates a System V shared memory segment.
shmctl integer System V shared memory control.
shmat integer Attach the System V shared memory segment to the address space of the calling process.
shmdt integer Detach the System V shared memory segment from the address space of the calling process.
socket integer Create an endpoint for communication.
socketpair integer Create a pair of connected sockets.
bind integer Bind a name to a socket.
listen integer Listen for connections on a socket.
accept integer Accept a connection on a socket.
connect integer Initiate a connection on a socket.
getsockname integer Get socket name.
getpeername integer Get name of connected peer socket.
sendto integer Send a message on a socket.
recvfrom integer Receive a message from a socket.
setsockopt integer Set options on sockets.
getsockopt integer Get options on sockets.
shutdown integer Shut down part of a full-duplex connection.
sendmsg integer Send a message on a socket using a message structure.
recvmsg integer Receive a message from a socket using a message structure.
readahead integer Initiate readahead on a file descriptor.
brk integer Change data segment size.
munmap integer Unmap files or devices into memory.
mremap integer Remap a virtual memory address.
add_key integer Add a key to the kernel's key management facility.
request_key integer Request a key from the kernel's key management facility.
keyctl integer Manipulate the kernel's key management facility.
clone integer Create a child process.
execve integer Execute a program.
rt_tgsigqueueinfo integer Send a real-time signal with data to a thread group.
perf_event_open integer Set up performance monitoring.
accept4 integer Accept a connection on a socket with flags.
recvmmsg integer Receive multiple messages from a socket.
prlimit64 integer Get and set resource limits.
fanotify_init integer Create and initialize fanotify group.
fanotify_mark integer Add, remove, or modify an fanotify mark on a filesystem object.
syncfs integer Commit filesystem caches to disk for a specific filesystem.
setns integer Reassociate thread with a namespace.
sendmmsg integer Send multiple messages on a socket.
process_vm_readv integer Read from another process's memory.
process_vm_writev integer Write to another process's memory.
kcmp integer Compare two processes to determine if they share a kernel resource.
finit_module integer Load a kernel module from a file descriptor.
sched_setattr integer Set scheduling policy and attributes for a thread.
sched_getattr integer Get scheduling policy and attributes for a thread.
renameat2 integer Rename a file or directory, with flags.
seccomp integer Operate on Secure Computing state of the process.
getrandom integer Obtain a series of random bytes.
memfd_create integer Create an anonymous file.
bpf integer Perform a BPF operation.
execveat integer Execute a program relative to a directory file descriptor.
userfaultfd integer Create a file descriptor for handling page faults in user space.
membarrier integer Issue memory barriers.
mlock2 integer Lock memory with flags.
copy_file_range integer Copy a range of data from one file to another.
preadv2 integer Read data into multiple buffers from a given offset, with flags.
pwritev2 integer Write data from multiple buffers at a given offset, with flags.
pkey_mprotect integer Set protection on a region of memory, with a protection key.
pkey_alloc integer Allocate a protection key.
pkey_free integer Free a protection key.
statx integer Get file status (extended).
rseq integer Restartable sequences.
kexec_file_load integer Load a new kernel for later execution from a file descriptor.
pidfd_send_signal integer Send a signal to a process specified by a PID file descriptor.
io_uring_setup integer Setup an io_uring instance.
io_uring_enter integer Register files or submit I/O to an io_uring instance.
io_uring_register integer Register files or user buffers for an io_uring instance.
open_tree integer Open a filesystem object by path and attribute.
move_mount integer Move a mount.
fsopen integer Open a filesystem by name and flags.
fsconfig integer Configure a filesystem.
fsmount integer Mount a filesystem.
fspick integer Select a filesystem by fd and path.
pidfd_open integer Obtain a file descriptor that refers to a process.

--- Conditional on __ARCH_WANT_TIME32_SYSCALLS or __BITS_PER_LONG != 32 ---
io_getevents integer Read asynchronous I/O events from the completion queue.
pselect6 integer Synchronous I/O multiplexing with a timeout and a signal mask.
ppoll integer Wait for some event on a file descriptor with a timeout and a signal mask.
timerfd_settime integer Arm or disarm a timer that notifies via a file descriptor.
timerfd_gettime integer Get current setting of a timer that notifies via a file descriptor.
utimensat integer Change file last access and modification times relative to a directory file descriptor.
futex integer Fast user-space locking.
nanosleep integer High-resolution sleep.
timer_gettime integer Get POSIX per-process timer.
timer_settime integer Arm/disarm POSIX per-process timer.
clock_settime integer Set time of a specified clock.
clock_gettime integer Get time of a specified clock.
clock_getres integer Get resolution of a specified clock.
clock_nanosleep integer High-resolution sleep with a specific clock.
rt_sigtimedwait integer Synchronously wait for queued real-time signals.
gettimeofday integer Get time.
settimeofday integer Set time.
adjtimex integer Tune kernel clock.
semtimedop integer System V semaphore operations with timeout.
wait4 integer Wait for process state changes, BSD style.
clock_adjtime integer Tune a specified clock.
io_pgetevents integer Read AIO events with timeout and signal mask.

--- Conditional on __ARCH_WANT_RENAMEAT ---
renameat integer Rename a file or directory relative to directory file descriptors.

--- Conditional on __ARCH_WANT_SYNC_FILE_RANGE2 ---
sync_file_range2 integer Sync a file segment with disk, with flags.

--- Conditional on !__ARCH_WANT_SYNC_FILE_RANGE2 (else part) ---
sync_file_range integer Sync a file segment with disk.

--- Conditional on __ARCH_WANT_SET_GET_RLIMIT ---
getrlimit integer Get resource limits.
setrlimit integer Set resource limits.

--- Conditional on !__ARCH_NOMMU ---
swapon integer Start swapping to a file or block device.
swapoff integer Stop swapping to a file or block device.
mprotect integer Set protection on a region of memory.
msync integer Synchronize a file with a memory map.
mlock integer Lock memory.
munlock integer Unlock memory.
mlockall integer Lock all pages mapped into the address space of the calling process.
munlockall integer Unlock all pages mapped into the address space of the calling process.
mincore integer Determine whether pages are resident in memory.
madvise integer Give advice about use of memory.
remap_file_pages integer Create a nonlinear file mapping.
mbind integer Set memory policy for a memory range.
get_mempolicy integer Retrieve NUMA memory policy for a thread.
set_mempolicy integer Set NUMA memory policy for a thread.
migrate_pages integer Migrate pages of the calling process to a set of nodes.
move_pages integer Move pages of the calling process to specific nodes.

--- Conditional on __SYSCALL_COMPAT or __BITS_PER_LONG == 32 ---
clock_gettime64 integer Get time of a specified clock (64-bit time_t).
clock_settime64 integer Set time of a specified clock (64-bit time_t).
clock_adjtime64 integer Tune a specified clock (64-bit time_t).
clock_getres_time64 integer Get resolution of a specified clock (64-bit time_t).
clock_nanosleep_time64 integer High-resolution sleep with a specific clock (64-bit time_t).
timer_gettime64 integer Get POSIX per-process timer (64-bit time_t).
timer_settime64 integer Arm/disarm POSIX per-process timer (64-bit time_t).
timerfd_gettime64 integer Get current setting of a timerfd (64-bit time_t).
timerfd_settime64 integer Arm or disarm a timerfd (64-bit time_t).
utimensat_time64 integer Change file timestamps relative to a directory fd (64-bit time_t).
pselect6_time64 integer Synchronous I/O multiplexing (64-bit time_t).
ppoll_time64 integer Wait for some event on a file descriptor (64-bit time_t).
io_pgetevents_time64 integer Read AIO events with timeout and signal mask (64-bit time_t).
recvmmsg_time64 integer Receive multiple messages from a socket (64-bit time_t).
mq_timedsend_time64 integer Send a message to a POSIX message queue with timeout (64-bit time_t).
mq_timedreceive_time64 integer Receive a message from a POSIX message queue with timeout (64-bit time_t).
semtimedop_time64 integer System V semaphore operations with timeout (64-bit time_t).
rt_sigtimedwait_time64 integer Synchronously wait for queued real-time signals (64-bit time_t).
futex_time64 integer Fast user-space locking (64-bit time_t).
sched_rr_get_interval_time64 integer Get the SCHEDRR interval for the named process (64-bit timet).

--- Conditional on __ARCH_WANT_SYS_CLONE3 ---
clone3 integer Create a child process with a new API.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0) ---
close_range integer Close a range of file descriptors.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 6, 0) ---
openat2 integer Open or create a file relative to a directory file descriptor, with extended flags.
pidfd_getfd integer Obtain a duplicate of another process's file descriptor.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) ---
faccessat2 integer Check user's permissions for a file relative to a directory fd, with flags.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 10, 0) ---
process_madvise integer Give advice about use of memory to a process.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 11, 0) ---
epoll_pwait2 integer Wait for an I/O event on an epoll file descriptor, with extended timeout.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) ---
mount_setattr integer Change properties of a mount.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 14, 0) ---
quotactl_fd integer Manipulate disk quotas using a file descriptor.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 13, 0) ---
landlock_create_ruleset integer Create a new Landlock ruleset.
landlock_add_rule integer Add a new rule to a Landlock ruleset.
landlock_restrict_self integer Enforce a Landlock ruleset on the calling thread.

--- Conditional on __ARCH_WANT_MEMFD_SECRET ---
memfd_secret integer Create an anonymous file in RAM for secrets.

--- Conditional on LINUX_VERSION_CODE >= KERNEL_VERSION(5, 15, 0) ---
process_mrelease integer Release memory of a remote process.

--- Conditional on __BITS_PER_LONG == 64 and !__SYSCALL_COMPAT ---
fcntl integer Manipulate file descriptor.
statfs integer Get filesystem statistics.
fstatfs integer Get filesystem statistics for an open file.
truncate integer Truncate a file to a specified length.
ftruncate integer Truncate an open file to a specified length.
lseek integer Reposition read/write file offset.
sendfile integer Transfer data between file descriptors.
newfstatat integer Get file status relative to a directory fd (new stat struct).
fstat integer Get file status for an open file (new stat struct).
mmap integer Map files or devices into memory.
fadvise64 integer Predeclare an access pattern for file data.
stat integer Get file status.
lstat integer Get symbolic link status.

--- Conditional on __BITS_PER_LONG != 64 or __SYSCALL_COMPAT (else part of above) ---
fcntl64 integer Manipulate file descriptor (64-bit version).
statfs64 integer Get filesystem statistics (64-bit version).
fstatfs64 integer Get filesystem statistics for an open file (64-bit version).
truncate64 integer Truncate a file to a specified length (64-bit version).
ftruncate64 integer Truncate an open file to a specified length (64-bit version).
llseek integer Reposition read/write file offset (long long version).
sendfile64 integer Transfer data between file descriptors (64-bit version).
fstatat64 integer Get file status relative to a directory fd (64-bit stat struct).
fstat64 integer Get file status for an open file (64-bit stat struct).
mmap2 integer Map files or devices into memory (with offset in pages).
fadvise64_64 integer Predeclare an access pattern for file data (64-bit offset/len).
stat64 integer Get file status (64-bit stat struct).
lstat64 integer Get symbolic link status (64-bit stat struct).

Lunatik

Contents

Modules

Topics

Module `syscall`

syscall

syscall

Parameters:

Returns:

Raises:

Usage:

Fields:

Lunatik

Contents

Modules

Topics

Module syscall

syscall

syscall

Parameters:

Returns:

Raises:

Usage:

Fields:

Module `syscall`