x86_64 LInux Syscall Reference

Linux x86_64 System Call Reference Table

This document serves as a reference to the system calls within the x86_64 Linux Kernel.

x86_64 Linux Syscall Structure

Instruction Syscall # Return Value arg0 arg1 arg2 arg3 arg4 arg5
SYSCALL rax rax rdi rsi rdx r10 r8 r9

x86_64 Linux Syscall Table

rax System Call rdi rsi rdx r10 r8 r9
0 sys_read unsigned int fd char* buf size_t count
1 sys_write unsigned int fd const char* buf size_t count
2 sys_open const char* filename int flags int mode
3 sys_close unsigned int fd
4 sys_stat const char* filename struct stat* statbuf
5 sys_fstat unsigned int fd struct stat* statbuf
6 sys_lstat const char* filename struct stat* statbuf
7 sys_poll struct poll_fd* ufds unsigned int nfds long timeout_msecs
8 sys_lseek unsigned int fd off_t offset unsigned int origin
9 sys_mmap unsigned long addr unsigned long len unsigned long prot unsigned long flags unsigned long fd unsigned long off
10 sys_mprotect unsigned long start size_t len unsigned long prot
11 sys_munmap unsigned long addr size_t len
12 sys_brk unsigned long brk
13 sys_rt_sigaction int sig const struct sigaction* act struct sigaction* oact sizt_t sigsetsize
14 sys_rt_sigprocmask int how sigset_t* nset sigset_t* oset sizt_t sigsetsize
15 sys_rt_sigreturn unsigned long _unused
16 sys_ioctl unsigned int fd unsigned int cmd unsigned long arg
17 sys_pread64 unsigned long fd char* buf size_t count off_t pos
18 sys_pwrite64 unsigned int fd const char* fd sizt_t count off_t pos
19 sys_readv unsigned long fd const struct iovec* vec unsigned long vlen
20 sys_writev unsigned long fd const struct iovec* vec unsigned long vlen
21 sys_access const char* filename int mode
22 sys_pipe int* fields
23 sys_select int n fd_set* inp fd_set* outp fd_set* exp struct timeval* tvp
24 sys_sched_yield
25 sys_mremap unsigned long addr unsigned long old_len unsigned long new_len unsigned long flags unsigned long new_addr
26 sys_msync unsigned long start size_t len int flags
27 sys_mincore unsigned long start size_t len unsigned char* vec
28 sys_madvise unsigned long start sizt_t len_in int behavior
29 sys_shmget key_t key size_t size int shmflg
30 sys_shmat int shmid char* shmaddr int shmflg
31 sys_shmctl int shmid int cmd struct shmid_ds* buf
32 sys_dup unsigned int fields
33 sys_dup2 unsigned int oldfd unsigned int newfd
34 sys_pause
35 sys_nanosleep struct timespec* rqtp struct timespec* rmtp
36 sys_getitimer int which struct itimerval* value
37 sys_alarm unsigned int seconds
38 sys_setitimer int which struct itimerval* value struct itimerval* ovalue
39 sys_getpid
40 sys_sendfile int out_fd int in_fd off_t* offset size_t count
41 sys_socket int family int type int protocol
42 sys_connect int fd struct sockaddr* uservaddr int addrlen
43 sys_accept int fd struct sockaddr* upeer_sockaddr int upeer_addrlen
44 sys_sendto int fd void* buff size_t len unsigned int flags struct sockaddr* addr socklen_t addr_len
45 sys_recvfrom int fd void *ubuf size_t len unsigned int flags struct sockaddr* addr socklen_t* addr_len
46 sys_sendmsg int fd struct msghdr* msg unsigned int flags
47 sys_recvmsg int fd struct msghdr* msg unsigned int flags
48 sys_shutdown int fd int how
49 sys_bind int fd struct sockaddr* umyaddr int addrlen
50 sys_listen int fd int backlog
51 sys_getsockname int fd struct sockaddr* usockaddr int* usockaddr_len
52 sys_getpeername int fd struct sockaddr* usockaddr int* usockaddr_len
53 sys_socketpair int family int type int protocol int* usockvec
54 sys_setsockopt int fd int level int optname char* optval int optlen
55 sys_getsockopt int fd int level int optname char* optval int* optlen
56 sys_clone unsigned long clone_flags unsigned long newsp void* parent_tid void* child_tid unsigned int tid
57 sys_fork
58 sys_vfork
59 sys_execve const char* filename const char* argv[] const char* envp[]
60 sys_exit int error_code
61 sys_wait4 pid_t upid int* stat_addr int options struct rusage* ru
62 sys_kill pid_t pid int sig
63 sys_uname struct old_utsname* name
64 sys_semget key_t key int nsems int semflg
65 sys_semop int semid struct sembuf* tsops unsigned nsops
66 sys_semctl int semid int semnum int cmd union semun arg
67 sys_shmdt char* shmaddr
68 sys_msgget key_t key int msgflg
69 sys_msgsnd int msquid struct msgbuf* msgp size_t msgsz int msgflg
70 sys_msgrcv int msqid struct msgbuf* msgp size_t msgsz long msgtyp int msgflg
71 sys_msgctl int msqid int cmd struct msqid_ds* buf
72 sys_fcntl unsigned int fd unsigned int cmd unsigned long arg
73 sys_flock unsigned int fd unsigned int cmd
74 sys_fsync unsigned int fd
75 sys_fdatasync unsigned int fd
76 sys_truncate const char* path long length
77 sys_ftruncate unsigned int fd unsigned long length
78 sys_getdents unsigned int fd struct linux_dirent* dirent unsigned int count
79 sys_getcwd char* buf unsigned long size
80 sys_chdir const char* filename
81 sys_fchdir unsigned int fd
82 sys_rename const char* oldname const char* newname
83 sys_mkdir const char* pathname int mode
84 sys_rmdir const char* pathname
85 sys_creat const char* pathname int mode
86 sys_link const char* oldname const char* newname
87 sys_unlink const char* pathname
88 sys_symlink const char* oldname const char* newname
89 sys_readlink const char* path char* buf int bufsiz
90 sys_chmod const char* filename mode_t mode
91 sys_fchmod unsigned int fd mod_t mode
92 sys_chown const char* filename uid_t user gid_t group
93 sys_fchown unsigned int fd uid_t user gid_t group
94 sys_lchown const char* filename uid_t user guid_t group
95 sys_umask int mask
96 sys_gettimeofday struct timeval* tv struct timezone* tz
97 sys_getrlimit unsigned int resource struct rlimit* rlim
98 sys_getrusage int who struct rusage* ru
99 sys_sysinfo struct sysinfo* info
100 sys_times struct tms* tbuf
101 sys_ptrace long request long pid unsigned long addr unsigned long data
102 sys_getuid
103 sys_syslog int type char* buf int len
104 sys_getgid
105 sys_setuid uid_t uid
106 sys_setgid gid_t gid
107 sys_geteuid
108 sys_getegid
109 sys_setpgid pid_t pid
110 sys_getppid
111 sys_getpgrp
112 sys_setsid
113 sys_setreuid uid_t ruid uid_t euid
114 sys_setregid gid_t rgid gid_t egid
115 sys_getgroups int gidsetsize gid_t* grouplist
116 sys_setgroups int gidsetsize gid_t* grouplist
117 sys_setresuid uid_t* ruid uid_t* euid uid_t* suid
118 sys_getresuid uid_t* ruid uid_t* euid uid_t *suid
119 sys_setresgid gid_t rgid gid_t egid gid_t sgid
120 sys_getresgid gid_t* rgid gid_t* egid gid_t* sgid
121 sys_getpgid pid_t pid
122 sys_setfsuid uid_t uid
123 sys_setfsgid gid_t gid
124 sys_getsid pid_t pid
125 sys_capget cap_user_header_t header cap_user_data_t dataptr
126 sys_capset cap_user_header_t header const user_data_t data
127 sys_rt_sigpending sigset_t* set size_t sigsetsize
128 sys_sigtimedwait const sigset_t* uthese siginfo_t* uinfo const struct timespec* utf size_t sigsetsize
129 sys_rt_sigqueueinfo pid_t pid int sig siginfo_t* uinfo
130 sys_rt_sigsuspend sigset_t* unewset size_t sigsetsize
131 sys_sigaltstack const stack_t* uss stack_t* uoss
132 sys_utime char* filename struct utimbuf* times
133 sys_mknod const char* filename umode_t mode unsigned dev
134 sys_uselib const char* library
135 sys_personality unsigned int personality
136 sys_ustat unsigned dev struct ustat* ubuf
137 sys_statfs const char* pathname struct statfs* buf
138 sys_fstatfs unsigned int fd struct statfs* buf
139 sys_sysfs int option unsigned long arg1 unsigned long arg2
140 sys_getpriority int which int who
141 sys_setpriority int which int who int niceval
142 sys_sched_setparam pid_t pid struct sched_param* param
143 sys_sched_getparam pid_t pid struct sched_param* param
144 sys_sched_setscheduler pid_t pid int policy struct sched_param* param
145 sys_sched_getscheduler pid_t pid
146 sys_sched_get_priority_max int policy
147 sys_sched_get_policy_min int policy
148 sys_sched_rr_get_interval pid_t pid struct timespec* interval
149 sys_mlock unsigned long start size_t len
150 sys_munlock unsigned long start size_t len
151 sys_mlockall int flags
152 sys_munlockall
153 sys_vhangup
154 sys_modify_ldt int func void* ptr unsigned long bytecount
155 sys_pivot_root const char* new_root const char* put_old
156 sys_sysctl struct __sysctl_args* args
157 sys_prctl int option unsigned long arg2 unsigned long arg3 unsigned long arg4 unsigned long arg5
158 sys_arch_prctl struct task_struct* task int code unsigned long* addr
159 sys_adjtimex struct timex *txc_p
160 sys_setrlimit unsigned int resource struct rlimit* rlim
161 sys_chroot const char* filename
162 sys_sync
163 sys_acct const char* name
164 sys_settimeofday struct timeval* tv struct timezone* tz
165 sys_mount char* dev_name char* dir_name char* type unsigned long flags void* data
166 sys_umount2 const char* target int flags
167 sys_swapon const char* specialfile int swap_flags
168 sys_swapoff const char* specialfile
169 sys_reboot int magic1 int magic2 unsigned int cmd void* arg
170 sys_sethostname char* name int len
171 sys_setdomainname char* name int len
172 sys_iopl unsigned int level struct pt_regs* regs
173 sys_ioperm unsigned long from unsigned long num int turn_on
174 sys_create_module REMOVED IN Linux 2.6
175 sys_init_module void* umod unsigned long len const char* uargs
176 sys_delete_module const char* name_user unsigned int flags
177 sys_get_kernel_syms REMOVED IN Linux 2.6
178 sys_query_module REMOVED IN Linux 2.6
179 sys_quotactl unsigned int cmd const char* special quid_t id void* addr
180 sys_nfsservctl REMOVED IN Linux 3.1
181 sys_getpmsg UNIMPLEMENTED
182 sys_putpmsg UNIMPLEMENTED
183 sys_afs_syscall UNIMPLEMENTED
184 sys_tuxcall UNIMPLEMENTED
185 sys_security UNIMPLEMENTED
186 sys_gettid
187 sys_readahead int fd off_64t offset size_t count
188 sys_setxattr const char* pathname const char* name const void* value size_t size int flags
189 sys_lsetxattr const char* pathname const char* name const void* value size_t size int flags
190 sys_fsetxattr int fd const char* name const void& value size_t size int flags
191 sys_getxattr const char* pathname const char* name void *value size_t size
192 sys_lgetxattr const char* pathname const char* name void* value size_t size
193 sys_fgetxattr int fd const char* name void* value size_t size
194 sys_listxattr const char* pathname char* list size_t size
195 sys_llistxattr const char* pathname char* list size_t size
196 sys_flistxattr int fd char* list size_t size
197 sys_removexattr const char* pathname const char* name
198 sys_lremovexattr const char* pathname const char* name
199 sys_fremovexattr int fd const char* name
200 sys_tkill pid_t pid int sig
201 sys_time time_t* tloc
202 sys_futex u32* uaddr int op u32 val struct timespec* utime u32* uaddr2 u32 val3
203 sys_sched_setaffinity pid_t pid unsigned int len unsigned long* user_mask_ptr
204 sys_sched_getaffinity pid_t pid unsigned int len unsigned long* user_mask_ptr
205 sys_set_thread_area struct user_desc* u_info
206 sys_io_setup unsigned nr_events aio_context_t* ctxp
207 sys_io_destroy aio_context_t ctx
208 sys_io_getevents aio_context_t ctx_id long min_nr long nr struct io_event* events
209 sys_io_submit aio_context_t* ctx_id long nr struct iocb** iocbpp
210 sys_io_cancel aio_context_t* ctx_id struct iocb* iocb struct io_event* result
211 sys_get_thread_area struct user_desc* u_info
212 sys_lookup_dcookie u64 cookie64 long buf long len
213 sys_epoll_create int size
214 sys_epoll_ctl_old UNIMPLEMENTED
215 sys_epoll_wait_old UNIMPLEMENTED
216 sys_remap_file_pages unsigned long start unsigned long size unsigned long prot unsigned long pgoff unsigned long flags
217 sys_getdents64 unsigned int fd struct linux_dirent64* dirent unsigned int count
218 sys_set_tid_address int* tidptr
219 sys_restart_syscall
220 sys_semtimedop int semid struct sembuf* tsops unsigned nsops const struct timespec* timeout
221 sys_fadvise64 int fd off_t offset size_t len int advice
222 sys_timer_create const clockid_t which_clock struct sigevent* timer_event_spec timer_t* created_timer_id
223 sys_timer_settime timer_t timer_id int flags const struct itimerspec* new_setting struct itimerspec* old_setting
224 sys_timer_gettime timer_t timer_id struct itimerspec* setting
225 sys_timer_getoverrun timer_t timer_id
226 sys_timer_delete timer_t timer_id
227 sys_clock_settime const clockid_t which_clock const struct timespec* tp
228 sys_clock_gettime const clockid_t which_clock struct timespec* tp
229 sys_clock_getres const clockid_t which_clock struct timespect* tp
230 sys_clock_nanosleep const clockid_t which_clock int flags const struct timespec* rqtp struct timespec* rmtp
231 sys_exit_group int error_code
232 sys_epoll_wait int epfd struct epoll_event* events int maxevents int timeout
233 sys_epoll_ctl int epfd int op int fd struct epoll_event* event
234 sys_tgkill pid_t tgid pid_t pid int sig
235 sys_utimes char* filename struct timeval* utimes
236 sys_vserver UNIMPLEMENTED
237 sys_mbind unsigned long start unsigned long len unsigned long mode unsigned long *nmask unsigned long maxnode unsigned flags
238 sys_set_mempolicy int mode unsigned long* nmask unsigned long maxnode
239 sys_get_mempolicy int* policy unsigned long* nmask unsigned long maxnode unsigned long addr unsigned long flags
240 sys_mq_open const char* u_name int oflag mode_t mode struct mq_attr* u_attr
241 sys_mq_unlink const char* u_name
242 sys_mq_timedsend mqd_t mqdes const char* u_msg_ptr size_t msg_len unsigned int msg_prio const struct timespec* u_abs_timeout
243 sys_mq_timedreceive mqd_t mqdes char* u_msg_ptr size_t msg_len unsigned int* u_msg_prio const struct timespec* u_abs_timeout
244 sys_mq_notify mqd_t mqdes const struct sigevent* u_notification
245 sys_mq_getsetattr mqd_t mqdes const struct mq_attr* u_mqstat struct mq_attr* u_omqstat
246 sys_kexec_load unsigned long entry unsigned long nr_segments struct kexec_segment* segments unsigned long flags
247 sys_waitid int which pid_t upid struct siginfo* infop int options struct rusage* ru
248 sys_add_key const char* _type const char* _description const void* _payload size_t plen
249 sys_request_key const char* _type const char* _description const char* _callout_info key_serial_t destringid
250 sys_keyctl int option unsigned long arg2 unsigned long arg3 unsigned long arg4 unsigned long arg5
251 sys_ioprio_set int which int who int ioprio
252 sys_ioprio_get int which int who
253 sys_inotify_init
254 sys_inotify_add_watch int fd const char* pathname u32 mask
255 sys_inotify_rm_watch int fd int wd
256 sys_migrate_pages pid_t pid unsigned long maxnode const unsigned long* old_nodes const unsigned long* new_nodes
257 sys_openat int dfd const char* filename int flags int mode
258 sys_mkdirat int dfd const char* pathname int mode
259 sys_mknodat int dfd const char* filename int mode unsigned dev
260 sys_fchownat int dfd const char* filename uid_t user gid_t group int flag
261 sys_futimesat int dfd const char* filename struct timeval* utimes
262 sys_newfstatat int dfd const char* filename struct stat* statbuf int flag
263 sys_unlinkat int dfd const char* pathname int flag
264 sys_renameat int oldfd const char* oldname int newfd const char* newname
265 sys_linkat int oldfd const char* oldname int newfd const char* newname int flags
266 sys_symlinkat const char* oldname int newfd const char* newname
267 sys_readlinkat int dfd const char* pathname char* buf int bufsiz
268 sys_fchmodat int dfd const char* filename mode_t mode
269 sys_faccessat int dfd const char* filename int mode
270 sys_pselect6 int n fd_set* inp fd_set* outp fd_set* exp struct timespec* tsp void* sig
271 sys_ppoll struct pollfd* ufds unsigned int nfds struct timespec* tsp const sigset_t* sigmask size_t sigsetsize
272 sys_unshare unsigned long unshare_flags
273 sys_set_robust_list struct robust_list_head* head size_t len
274 sys_get_robust_list int pid struct robust_list_head** head_ptr size_t* len_ptr
275 sys_splice int fd_in off_t* off_in int fd_out off_t* off_out size_t len unsigned int flags
276 sys_tee int fdin int fdout size_t len unsigned int flags
277 sys_sync_file_range long fd off_t offset off_t bytes long flags
278 sys_vmsplice int fd const struct iovec* iov unsigned long nr_segs unsigned int flags
279 sys_move_pages pid_t pid unsigned long nr_pages const void** pages const int* nodes int* status int flags
280 sys_utimensat int dfd const char* filename struct timespec* utimes int flags
281 sys_epoll_wait int epfd struct epoll_event* events int maxevents int timeout const sigset_t* sigmask size_t sigsetsize
282 sys_signalfd int ufd sigset_t* user_mask size_t sizemask
283 sys_timerfd_create int clockid int flags
284 sys_eventfd unsigned int count
285 sys_fallocate long fd long mode off_t offset off_t len
286 sys_timerfd_settime int ufd int flags const struct itimerspec* utmr struct itimerspec* otmr
287 sys_timerfd_gettime int ufd struct itimerspec* otmr
288 sys_accept4 int fd struct sockaddr* upeer_sockaddr int* upeer_addrlen int flags
289 sys_signalfd4 int ufd sigset_t* user_mask size_t sizemask int flags
290 sys_eventfd2 unsigned int count int flags
291 sys_epoll_create1 int flags
292 sys_dup3 unsigned int oldfd unsigned int newfd int flags
293 sys_pipe2 int* filedes int flags
294 sys_inotify_init1 int flags
295 sys_preadv unsigned long fd const struct iovec* vec unsigned long vlen unsigned long pos_l unsigned long pos_h
296 sys_pwritev unsigned long fd const struct iovec* vec unsigned long vlen unsigned long pos_l unsigned long pos_h
297 sys_rt_tgsigqueueinfo pid_t tgid pid_t pid int sig siginfo_t* uinfo
298 sys_perf_event_open struct perf_event_attr* attr_uptr pid_t pid int cpu int group_fd unsigned long flags
299 sys_recvmmsg int fd struct msghdr* mmsg unsigned int vlen unsigned int flags struct timespec* timeout
300 sys_fanotify_init unsigned int flags unsigned int event_f_flags
301 sys_fanotify_mark long fanotify_fd long flags __u64 mask long dfd long pathname
302 sys_prlimit64 pid_t pid unsigned int resource const struct rlimit64* new_rlim struct rlimit64* old_rlim
303 sys_name_to_handle_at int dfd const char* name struct file_handle* handle int *mnt_id int flag
304 sys_open_by_handle_at int dfd const char* name struct file_handle* handle int *mnt_id int flags
305 sys_clock_adjtime clockid_t which_clock struct time* tx
306 sys_syncfs int fd
307 sys_sendmmsg int fd struct mmsghdr* mmsg unsigned int vlen unsigned int flags
308 sys_setns int fd struct mmsghdr* mmsg unsigned int vlen unsigned int flags
309 sys_getcpu unsigned* cpup unsigned* nodep struct getcpu_cache* unused
310 sys_process_vm_readv pid_t pid const struc iovec* lvec unsigned long liovcnt const struct iovec* rvec unsigned long riovcnt unsigned long flags
311 sys_process_vm_writev pid_t pid const struct iovec* lvec unsigned long liovcnt const struct iovcc* rvec unsigned long riovcnt unsigned long flags
312 sys_kcmp pid_t pid1 pid_t pid2 int type unsigned long idx1 unsigned long idx2
313 sys_finit_module int fd const char* param_values int flags
314 sys_sched_setattr pid_t pid struct sched_attr* attr unsigned int flags
315 sys_sched_getattr pid_t pid struct sched_attr* attr unsigned int size unsigned int flags
316 sys_renameat2 int olddfd const char* oldname int newdfd const char* newname unsigned int flags
317 sys_seccomp unsigned int op unsigned int flags const char *uargs
318 sys_getrandom char* buf size_t count unsigned int flags
319 sys_memfd_create const char* uname_ptr unsigned int flags
320 sys_kexec_file_load int kernel_fd int initrd_fd unsigned long cmdline_len const char* cmdline_ptr unsigned long flags
321 sys_bpf int cmd union bpf_attr* attr unsigned int size
322 stub_execveat int dfd const char* filename const char* argv const char* envp int flags
323 userfaultfd int flags
324 membarrier int cmd int flags
325 mlock2 unsigned long start size_t len int flags
326 copy_file_range int fd_in off_t* off_in int fd_out off_t* off_out size_t len unsigned int flags
327 preadb2 unsigned long fd const struct iovec* vec unsigned long vlen unsigned long pos_l unsigned long pos_h int flags
328 pwritev2 unsigned long fd const struct iovec* vec unsigned long vlen unsigned long pos_l unsigned long pos_h int flags
329 pkey_mprotect
330 pkey_alloc
331 pkey_free
332 statx
333 io_pgetevents
334 rseq
335 pkey_mprotect

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