Syscall Reference

Complete reference for all Strat9 OS syscalls. Syscalls are invoked via the syscall instruction (x86_64). Arguments are passed in registers; the return value is in RAX.

ABI convention: Success returns a non-negative value. Errors return a negative errno value (two's complement). Userspace checks if result > 0xFFFF_F000 to detect errors, then applies !result + 1 to get the errno number.

Constants

AT_* flags (for *at syscalls)

Constant	Value	Description
`AT_FDCWD`	`-100`	Use the process's current working directory as the base directory
`AT_REMOVEDIR`	`0x200`	Remove a directory (for `SYS_UNLINKAT`)
`AT_SYMLINK_NOFOLLOW`	`0x100`	Do not follow symbolic links (for `SYS_FSTATAT`)
`AT_EMPTY_PATH`	`0x1000`	Operate on the fd itself when path is empty

Open flags

Flag	Value	Description
`O_RDONLY`	`0`	Open for reading
`O_WRONLY`	`1`	Open for writing
`O_RDWR`	`2`	Open for reading and writing
`O_CREAT`	`0x40`	Create file if it does not exist
`O_EXCL`	`0x800`	Fail if file already exists (with O_CREAT)
`O_TRUNC`	`0x200`	Truncate file to zero length
`O_APPEND`	`0x400`	Append to end of file
`O_NONBLOCK`	`0x800`	Non-blocking mode
`O_DIRECTORY`	`0x10000`	Open as directory
`O_NOFOLLOW`	`0x20000`	Do not follow symlinks

Protection flags (mmap)

Flag	Value	Description
`PROT_READ`	`1`	Page can be read
`PROT_WRITE`	`2`	Page can be written
`PROT_EXEC`	`4`	Page can be executed

Signal constants

Constant	Value	Description
`SIG_DFL`	`0`	Default signal handling
`SIG_IGN`	`1`	Ignore signal
`SIG_BLOCK`	`0`	Block signals in set
`SIG_UNBLOCK`	`1`	Unblock signals in set
`SIG_SETMASK`	`2`	Set signal mask to set

Waitpid options

Flag	Value	Description
`WNOHANG`	`1`	Return immediately if no child has exited
`WUNTRACED`	`2`	Also return for stopped children
`WCONTINUED`	`4`	Also return for continued children

Clock IDs

Constant	Value	Description
`CLOCK_REALTIME`	`0`	System-wide real-time clock
`CLOCK_MONOTONIC`	`1`	Monotonic clock (not affected by adjustments)
`CLOCK_PROCESS_CPUTIME_ID`	`2`	Per-process CPU time
`CLOCK_THREAD_CPUTIME_ID`	`3`	Per-thread CPU time

Handle operations

#	Syscall	Parameters	Return	Description
0	`SYS_NULL`	:	0	No-op (used for benchmarking)
1	`SYS_HANDLE_DUPLICATE`	`handle: u64`	new handle	Duplicate a capability handle
2	`SYS_HANDLE_CLOSE`	`handle: u64`	0	Close a capability handle
3	`SYS_HANDLE_WAIT`	`handle: u64, timeout_ns: u64`	0	Wait on a handle (blocks until ready or timeout)
4	`SYS_HANDLE_GRANT`	`handle: u64, target_pid: u64`	0	Grant a capability to another process
5	`SYS_HANDLE_REVOKE`	`handle: u64`	0	Revoke a capability (all holders lose access)
6	`SYS_HANDLE_INFO`	`handle: u64, out_ptr: u64`	0	Query capability info (writes `HandleInfo` struct)

Errors: EBADF (invalid handle), EPERM (no grant permission), ESRCH (target process not found)

Memory management

#	Syscall	Parameters	Return	Description
100	`SYS_MMAP`	`addr: u64, len: u64, prot: u64, flags: u64, fd: u64, offset: u64`	mapped address	Map a memory region
101	`SYS_MUNMAP`	`addr: u64, len: u64`	0	Unmap a memory region
102	`SYS_BRK`	`addr: u64`	new break	Set/clear the data break
103	`SYS_MREMAP`	`old_addr: u64, old_len: u64, new_len: u64, flags: u64, new_addr: u64`	new address	Remap a memory region
104	`SYS_MPROTECT`	`addr: u64, len: u64, prot: u64`	0	Change memory protection flags
105	`SYS_MEM_REGION_EXPORT`	`addr: u64, len: u64`	region handle	Export a memory region as a shareable handle
106	`SYS_MEM_REGION_MAP`	`region_handle: u64, addr: u64, len: u64`	mapped address	Map an exported memory region
107	`SYS_MEM_REGION_INFO`	`region_handle: u64, out_ptr: u64`	0	Query region metadata

Prot flags: PROT_READ (1), PROT_WRITE (2), PROT_EXEC (4)

Errors: EINVAL (bad alignment/flags), ENOMEM (out of memory), EACCES (permission denied), EEXIST (region already mapped)

IPC : Ports

#	Syscall	Parameters	Return	Description
200	`SYS_IPC_CREATE_PORT`	:	port handle	Create a new IPC port
201	`SYS_IPC_SEND`	`port_handle: u64, msg_ptr: u64, msg_len: u64`	0	Send a message to a port
202	`SYS_IPC_RECV`	`port_handle: u64, buf_ptr: u64, buf_len: u64`	bytes received	Receive a message (blocks)
203	`SYS_IPC_CALL`	`port_handle: u64, msg_ptr: u64, msg_len: u64`	bytes received	Synchronous RPC (send + wait for reply)
204	`SYS_IPC_REPLY`	`msg_ptr: u64, msg_len: u64`	0	Reply to the current IPC call
205	`SYS_IPC_BIND_PORT`	`port_handle: u64`	0	Bind a port as a listener
206	`SYS_IPC_UNBIND_PORT`	`port_handle: u64`	0	Unbind a listening port
207	`SYS_IPC_TRY_RECV`	`port_handle: u64, buf_ptr: u64, buf_len: u64`	bytes received (0 if empty)	Non-blocking receive
208	`SYS_IPC_CONNECT`	`port_handle: u64`	0	Connect to a bound port
210	`SYS_IPC_RING_CREATE`	`size_log2: u64`	ring handle	Create a shared ring buffer
211	`SYS_IPC_RING_MAP`	`ring_handle: u64, addr: u64`	0	Map a shared ring into address space

Errors: EBADF (invalid handle), ENOSPC (ring full), EAGAIN (non-blocking, nothing available), ETIMEDOUT (timeout exceeded)

IPC : Channels (typed MPMC)

#	Syscall	Parameters	Return	Description
220	`SYS_CHAN_CREATE`	`capacity: u64`	channel handle	Create a typed channel
221	`SYS_CHAN_SEND`	`handle: u64, msg_ptr: u64`	0	Send a message (blocks if full)
222	`SYS_CHAN_RECV`	`handle: u64, msg_ptr: u64`	0	Receive a message (blocks if empty)
223	`SYS_CHAN_TRY_RECV`	`handle: u64, msg_ptr: u64`	1 if received, 0 if empty	Non-blocking receive
224	`SYS_CHAN_CLOSE`	`handle: u64`	0	Close channel handle

Errors: EBADF (invalid handle), EPIPE (all endpoints disconnected), EAGAIN (try_recv on empty channel)

IPC : Semaphores

#	Syscall	Parameters	Return	Description
230	`SYS_SEM_CREATE`	`initial_value: u64`	semaphore handle	Create a counting semaphore
231	`SYS_SEM_WAIT`	`handle: u64`	0	Decrement (blocks if zero)
232	`SYS_SEM_TRYWAIT`	`handle: u64`	1 if acquired, 0 if would block	Non-blocking decrement
233	`SYS_SEM_POST`	`handle: u64`	0	Increment (wake a waiter)
234	`SYS_SEM_CLOSE`	`handle: u64`	0	Close semaphore handle

Errors: EBADF (invalid handle), EAGAIN (try_wait on zero semaphore)

PCI

#	Syscall	Parameters	Return	Description
240	`SYS_PCI_ENUM`	`criteria_ptr: u64, out_ptr: u64, max_count: u64`	device count	Enumerate PCI devices matching criteria
241	`SYS_PCI_CFG_READ`	`addr_ptr: u64, offset: u64, width: u64`	config value	Read PCI configuration register
242	`SYS_PCI_CFG_WRITE`	`addr_ptr: u64, offset: u64, width: u64, value: u64`	0	Write PCI configuration register

Errors: EINVAL (invalid width/offset), EACCES (no PCI capability)

Async I/O

#	Syscall	Parameters	Return	Description
250	`SYS_ASYNC_SETUP`	`handle: u64, event_mask: u64`	async context	Set up async notification on a handle
251	`SYS_ASYNC_ENTER`	`ctx: u64`	0	Enter async wait (yields until event)
252	`SYS_ASYNC_CANCEL`	`ctx: u64`	0	Cancel pending async wait
253	`SYS_ASYNC_MAP`	`ctx: u64, ring_handle: u64`	0	Map an event ring to the async context
254	`SYS_ASYNC_DESTROY`	`ctx: u64`	0	Destroy async context

Process management

#	Syscall	Parameters	Return	Description
300	`SYS_PROC_EXIT`	`exit_code: u64`	: (never returns)	Terminate current process
301	`SYS_PROC_YIELD`	:	0	Yield CPU to scheduler
302	`SYS_PROC_FORK`	`frame: &SyscallFrame`	child PID (parent), 0 (child)	Fork the current process (COW)
308	`SYS_PROC_GETPID`	:	process ID	Get current process ID
309	`SYS_PROC_GETPPID`	:	parent PID	Get parent process ID
310	`SYS_PROC_WAITPID`	`pid: i64, status_ptr: u64, options: u64`	child PID	Wait for a child process
311	`SYS_GETPID`	:	process ID	Alias for SYS_PROC_GETPID
312	`SYS_GETTID`	:	thread ID	Get current thread ID
314	`SYS_PROC_WAIT`	:	:	Wait for any child
315	`SYS_PROC_EXECVE`	`path_ptr: u64, path_len: u64, argv_ptr: u64, envp_ptr: u64`	: (replaces image)	Execute a new program
341	`SYS_THREAD_CREATE`	`entry: u64, stack: u64, arg: u64`	thread ID	Create a new thread
342	`SYS_THREAD_JOIN`	`tid: u64, status_ptr: u64`	0	Wait for thread to exit
343	`SYS_THREAD_EXIT`	`status: u64`	: (never returns)	Terminate current thread

Errors: ECHILD (no child processes), EAGAIN (thread creation failed), ENOMEM (out of memory)

Futex

#	Syscall	Parameters	Return	Description
303	`SYS_FUTEX_WAIT`	`addr: u64, val: u32, timeout_ns: u64`	0	Sleep if `*addr == val`
304	`SYS_FUTEX_WAKE`	`addr: u64, max_wake: u32`	woken count	Wake up to N waiters
305	`SYS_FUTEX_REQUEUE`	`addr: u64, max_wake: u32, addr2: u64, max_requeue: u32`	woken count	Wake + requeue to addr2
306	`SYS_FUTEX_CMP_REQUEUE`	`addr: u64, max_wake: u32, addr2: u64, max_requeue: u32, cmp_val: u32`	woken count	Conditional requeue
307	`SYS_FUTEX_WAKE_OP`	`addr: u64, max_wake: u32, addr2: u64, max_requeue: u32, wake_op: u32`	woken count	Atomic op + wake

Errors: EAGAIN (value mismatch in WAIT), ETIMEDOUT (timeout expired), EFAULT (invalid address)

Signals

#	Syscall	Parameters	Return	Description
320	`SYS_KILL`	`pid: i64, signum: u32`	0	Send signal to a process
321	`SYS_SIGPROCMASK`	`how: i32, set_ptr: u64, oldset_ptr: u64`	0	Get/set signal mask
322	`SYS_SIGACTION`	`signum: u64, act_ptr: u64, oact_ptr: u64`	0	Set signal handler
323	`SYS_SIGALTSTACK`	`ss_ptr: u64, old_ss_ptr: u64`	0	Set alternate signal stack
324	`SYS_SIGPENDING`	`set_ptr: u64`	0	Get pending signals
325	`SYS_SIGSUSPEND`	`mask_ptr: u64`	: (restarted on signal)	Suspend until signal
326	`SYS_SIGTIMEDWAIT`	`set_ptr: u64, info_ptr: u64, timeout_ptr: u64`	signal number	Wait for specific signal
327	`SYS_SIGQUEUE`	`pid: i64, signum: u32, sigval_ptr: u64`	0	Queue a signal with data
328	`SYS_KILLPG`	`pgrp: u64, signum: u32`	0	Send signal to process group
352	`SYS_TGKILL`	`tgid: u64, tid: u64, signum: u32`	0	Send signal to specific thread
353	`SYS_RT_SIGRETURN`	:	:	Return from signal handler

Process groups & sessions

#	Syscall	Parameters	Return	Description
316	`SYS_FCNTL`	`fd: u64, cmd: u64, arg: u64`	depends on cmd	File control operations
317	`SYS_SETPGID`	`pid: u64, pgid: u64`	0	Set process group ID
318	`SYS_GETPGID`	`pid: u64`	pgid	Get process group ID
319	`SYS_SETSID`	:	session ID	Create new session
329	`SYS_GETITIMER`	`which: u64, out_ptr: u64`	0	Get interval timer
330	`SYS_SETITIMER`	`which: u64, in_ptr: u64, out_ptr: u64`	0	Set interval timer
331	`SYS_GETPGRP`	:	pgrp	Get current process group
332	`SYS_GETSID`	`pid: u64`	sid	Get session ID
333	`SYS_SET_TID_ADDRESS`	`tidptr: u64`	0	Set clear-on-exit TID address
334	`SYS_EXIT_GROUP`	`exit_code: u64`	: (never returns)	Exit all threads in process

User/group IDs

#	Syscall	Parameters	Return	Description
335	`SYS_GETUID`	:	uid	Get real user ID
336	`SYS_GETEUID`	:	euid	Get effective user ID
337	`SYS_GETGID`	:	gid	Get real group ID
338	`SYS_GETEGID`	:	egid	Get effective group ID
339	`SYS_SETUID`	`uid: u64`	0	Set user ID
340	`SYS_SETGID`	`gid: u64`	0	Set group ID

Misc process

#	Syscall	Parameters	Return	Description
344	`SYS_UNAME`	`uts_ptr: u64`	0	Get system information (name, release, etc.)
350	`SYS_ARCH_PRCTL`	`code: u64, addr: u64`	0	Architecture-specific process control

File I/O

#	Syscall	Parameters	Return	Description
403	`SYS_OPEN`	`path_ptr: u64, path_len: u64, flags: u64`	file descriptor	Open a file
404	`SYS_WRITE`	`fd: u64, buf_ptr: u64, buf_len: u64`	bytes written	Write to a file descriptor
405	`SYS_READ`	`fd: u64, buf_ptr: u64, buf_len: u64`	bytes read	Read from a file descriptor
406	`SYS_CLOSE`	`fd: u64`	0	Close a file descriptor
407	`SYS_LSEEK`	`fd: u64, offset: u64, whence: u64`	new position	Seek in a file
408	`SYS_FSTAT`	`fd: u64, stat_ptr: u64`	0	Get file status (fstat)
409	`SYS_STAT`	`path_ptr: u64, path_len: u64, stat_ptr: u64`	0	Get file status by path
413	`SYS_ACCESS`	`path_ptr: u64, path_len: u64, mode: u64`	0	Check file accessibility (uses effective UID/GID, not real). Prefer `SYS_FACCESSAT` for new code.
430	`SYS_GETDENTS`	`fd: u64, buf_ptr: u64, buf_len: u64`	bytes read	Read directory entries
431	`SYS_PIPE`	`fds_ptr: u64`	0	Create a pipe pair
432	`SYS_DUP`	`old_fd: u64`	new fd	Duplicate file descriptor
433	`SYS_DUP2`	`old_fd: u64, new_fd: u64`	new fd	Duplicate to specific fd
456	`SYS_PREAD`	`fd: u64, buf_ptr: u64, buf_len: u64, offset: u64`	bytes read	Pread at offset
457	`SYS_PWRITE`	`fd: u64, buf_ptr: u64, buf_len: u64, offset: u64`	bytes written	Pwrite at offset

Open flags: O_RDONLY (0), O_WRONLY (1), O_RDWR (2), O_CREAT (0x40), O_TRUNC (0x200), O_APPEND (0x400), O_EXCL (0x800)

Errors: ENOENT (file not found), EACCES (permission denied), EBADF (bad fd), ENOTDIR (not a directory), EISDIR (is a directory), ENOSPC (disk full), EIO (I/O error)

File system operations

#	Syscall	Parameters	Return	Description
440	`SYS_CHDIR`	`path_ptr: u64, path_len: u64`	0	Change working directory
441	`SYS_FCHDIR`	`fd: u64`	0	Change working directory by fd
442	`SYS_GETCWD`	`buf_ptr: u64, buf_len: u64`	bytes written	Get current working directory
443	`SYS_IOCTL`	`fd: u64, cmd: u64, arg: u64`	depends on cmd	Device I/O control
444	`SYS_UMASK`	`mask: u64`	old mask	Set file mode creation mask
445	`SYS_UNLINK`	`path_ptr: u64, path_len: u64`	0	Delete a file
446	`SYS_RMDIR`	`path_ptr: u64, path_len: u64`	0	Remove a directory
447	`SYS_MKDIR`	`path_ptr: u64, path_len: u64, mode: u64`	0	Create a directory
448	`SYS_RENAME`	`old_ptr: u64, old_len: u64, new_ptr: u64, new_len: u64`	0	Rename a file
449	`SYS_LINK`	`old_ptr: u64, old_len: u64, new_ptr: u64, new_len: u64`	0	Create a hard link
450	`SYS_SYMLINK`	`target_ptr: u64, target_len: u64, link_ptr: u64, link_len: u64`	0	Create a symbolic link
451	`SYS_READLINK`	`path_ptr: u64, path_len: u64, buf_ptr: u64, buf_len: u64`	bytes read	Read symbolic link target
452	`SYS_CHMOD`	`path_ptr: u64, path_len: u64, mode: u64`	0	Change file permissions
453	`SYS_FCHMOD`	`fd: u64, mode: u64`	0	Change file permissions by fd
454	`SYS_TRUNCATE`	`path_ptr: u64, path_len: u64, len: u64`	0	Truncate a file
455	`SYS_FTRUNCATE`	`fd: u64, len: u64`	0	Truncate a file by fd

`*at` variants (relative to directory fd)

These syscalls resolve paths relative to a directory file descriptor instead of the process CWD. They are the POSIX-standard way to open, stat, and manipulate files safely in multi-threaded programs.

Special `dirfd` values

Value	Constant	Meaning
`-100`	`AT_FDCWD`	Use the process's current working directory (CWD) as the base
`≥ 0`	valid fd	Use the opened directory referenced by this file descriptor

Syscall reference

#	Syscall	Parameters	Return	Description
462	`SYS_OPENAT`	`dirfd: u64, path_ptr: u64, path_len: u64, flags: u64`	file descriptor	Open a file relative to `dirfd`. If `path_ptr` is absolute, `dirfd` is ignored.
463	`SYS_FSTATAT`	`dirfd: u64, path_ptr: u64, path_len: u64, stat_ptr: u64, flags: u64`	0	Get file status relative to `dirfd`. `stat_ptr` receives a `FileStat` struct.
464	`SYS_UNLINKAT`	`dirfd: u64, path_ptr: u64, path_len: u64, flags: u64`	0	Delete a file relative to `dirfd`. If `AT_REMOVEDIR` flag is set, removes a directory.
465	`SYS_RENAMEAT`	`olddirfd: u64, old_ptr: u64, old_len: u64, newdirfd: u64, new_ptr: u64, new_len: u64`	0	Rename/move a file. Source and destination can have different base directories.
466	`SYS_MKDIRAT`	`dirfd: u64, path_ptr: u64, path_len: u64, mode: u64`	0	Create a directory relative to `dirfd`.
467	`SYS_READLINKAT`	`dirfd: u64, path_ptr: u64, path_len: u64, buf_ptr: u64, buf_len: u64`	bytes read	Read the target of a symbolic link relative to `dirfd`.
468	`SYS_FACCESSAT`	`dirfd: u64, path_ptr: u64, path_len: u64, mode: u64, flags: u64`	0	Check file accessibility. `mode`: `R_OK (4)`, `W_OK (2)`, `X_OK (1)`, `F_OK (0)`.

Flags

Flag	Value	Description
`AT_FDCWD`	`-100`	Use process CWD as base directory
`AT_REMOVEDIR`	`0x200`	Unlink a directory instead of a file (for `SYS_UNLINKAT`)
`AT_SYMLINK_NOFOLLOW`	`0x100`	Do not follow symlinks (for `SYS_FSTATAT`)
`AT_EMPTY_PATH`	`0x1000`	Operate on `dirfd` itself when path is empty

Errors

EBADF (invalid dirfd), ENOENT (path not found), EACCES (permission denied), ENOTDIR (dirfd is not a directory), EEXIST (file exists for CREATE_EXCL), EINVAL (invalid flags)

Poll / I/O multiplexing

#	Syscall	Parameters	Return	Description
460	`SYS_POLL`	`fds_ptr: u64, nfds: u64, timeout_ms: i64`	ready count	Poll file descriptors
461	`SYS_PPOLL`	`fds_ptr: u64, nfds: u64, timeout_ptr: u64, sigmask_ptr: u64`	ready count	Ppoll with signal mask

Network

#	Syscall	Parameters	Return	Description
410	`SYS_NET_RECV`	`buf_ptr: u64, buf_len: u64`	bytes received	Receive network packet
411	`SYS_NET_SEND`	`buf_ptr: u64, buf_len: u64`	bytes sent	Send network packet
412	`SYS_NET_INFO`	`info_type: u64, buf_ptr: u64`	0	Query network info (IP, gateway, etc.)

Volume (block device)

#	Syscall	Parameters	Return	Description
420	`SYS_VOLUME_READ`	`handle: u64, offset: u64, buf_ptr: u64, buf_len: u64`	bytes read	Read from volume
421	`SYS_VOLUME_WRITE`	`handle: u64, offset: u64, buf_ptr: u64, buf_len: u64`	bytes written	Write to volume
422	`SYS_VOLUME_INFO`	`handle: u64, out_ptr: u64`	0	Query volume info

Time

#	Syscall	Parameters	Description
500	`SYS_CLOCK_GETTIME`	`clock_id: u64, tp_ptr: u64`	Get clock time
501	`SYS_NANOSLEEP`	`req_ptr: u64, rem_ptr: u64`	Sleep for a duration
502	`SYS_CLOCK_NANOSLEEP`	`clock_id: u64, flags: u64, req_ptr: u64, rem_ptr: u64`	Sleep on a specific clock

Clock IDs: CLOCK_REALTIME (0), CLOCK_MONOTONIC (1), CLOCK_PROCESS_CPUTIME_ID (2), CLOCK_THREAD_CPUTIME_ID (3)

Debug & miscellaneous

#	Syscall	Parameters	Return	Description
600	`SYS_DEBUG_LOG`	`msg_ptr: u64, msg_len: u64`	0	Write a debug message to kernel log
601	`SYS_GETRANDOM`	`buf: u64, len: usize, flags: u32`	bytes written	Fill buffer with random bytes
610	`SYS_SET_ROBUST_LIST`	`head: u64, len: usize`	0	Set robust futex list head
611	`SYS_GET_ROBUST_LIST`	`pid: i64, head_ptr: u64, len_ptr: u64`	0	Get robust futex list head

Module management

#	Syscall	Parameters	Return	Description
700	`SYS_MODULE_LOAD`	`path_ptr: u64, path_len: u64`	module ID	Load a kernel module
701	`SYS_MODULE_UNLOAD`	`module_id: u64`	0	Unload a kernel module
702	`SYS_MODULE_GET_SYMBOL`	`module_id: u64, name_ptr: u64, name_len: u64`	symbol address	Look up a symbol in a loaded module
703	`SYS_MODULE_QUERY`	`out_ptr: u64, max_count: u64`	module count	List loaded modules

Silo management

#	Syscall	Parameters	Return	Description
800	`SYS_SILO_CREATE`	:	silo ID	Create a new silo
801	`SYS_SILO_CONFIG`	`silo_id: u64, key_ptr: u64, key_len: u64, val_ptr: u64, val_len: u64`	0	Configure a silo
802	`SYS_SILO_ATTACH_MODULE`	`silo_id: u64, module_id: u64`	0	Attach a module to a silo
803	`SYS_SILO_START`	`silo_id: u64`	0	Start a silo
804	`SYS_SILO_STOP`	`silo_id: u64`	0	Stop a silo
805	`SYS_SILO_KILL`	`silo_id: u64`	0	Kill a silo (force stop)
806	`SYS_SILO_EVENT_NEXT`	`silo_id: u64, out_ptr: u64`	0	Wait for next silo event
807	`SYS_SILO_SUSPEND`	`silo_id: u64`	0	Suspend a silo
808	`SYS_SILO_RESUME`	`silo_id: u64`	0	Resume a silo
809	`SYS_SILO_PLEDGE`	`promises_ptr: u64, promises_len: u64`	0	Restrict syscalls (pledge)
810	`SYS_SILO_UNVEIL`	`path_ptr: u64, path_len: u64, perms_ptr: u64, perms_len: u64`	0	Restrict filesystem access (unveil)
811	`SYS_SILO_ENTER_SANDBOX`	:	0	Enter sandbox mode (irreversible)
812	`SYS_SILO_RENAME`	`silo_id: u64, name_ptr: u64, name_len: u64`	0	Rename a silo

ABI version

#	Syscall	Parameters	Return	Description
900	`SYS_ABI_VERSION`	:	`(major << 16) \| minor`	Query ABI version

Common errno values

Value	Name	Description
1	`EPERM`	Operation not permitted
2	`ENOENT`	No such file or directory
3	`ESRCH`	No such process
4	`EINTR`	Interrupted system call
5	`EIO`	Input/output error
7	`E2BIG`	Argument list too long
9	`EBADF`	Bad file descriptor
10	`ECHILD`	No child processes
11	`EAGAIN`	Resource temporarily unavailable
12	`ENOMEM`	Out of memory
13	`EACCES`	Permission denied
14	`EFAULT`	Bad address
17	`EEXIST`	File exists
20	`ENOTDIR`	Not a directory
21	`EISDIR`	Is a directory
22	`EINVAL`	Invalid argument
28	`ENOSPC`	No space left on device
32	`EPIPE`	Broken pipe
38	`ENOSYS`	Function not implemented
52	`ENOTSUP`	Not supported
98	`EADDRINUSE`	Address already in use
110	`ETIMEDOUT`	Connection timed out
111	`ECONNREFUSED`	Connection refused

Strat9 OS documentation