IPC Protocol Labels

Every SYS_CALL or SYS_SEND that targets a server endpoint carries a 40-bit label in the message info word. The label tells the server which operation is being requested. This page is the full reference for the labels defined under lib/trona/uapi/protocol/, organized by server.

All eight files are included verbatim into substrate via substrate/protocol.rs, so every call site sees the same numeric constants at compile time:

pub mod vfs     { include!("../uapi/protocol/vfs.rs"); }
pub mod procmgr { include!("../uapi/protocol/procmgr.rs"); }
pub mod mmsrv   { include!("../uapi/protocol/mmsrv.rs"); }
pub mod namesrv { include!("../uapi/protocol/namesrv.rs"); }
pub mod posix   { include!("../uapi/protocol/posix.rs"); }
pub mod win32   { include!("../uapi/protocol/win32.rs"); }
pub mod server  { include!("../uapi/protocol/server.rs"); }
pub mod rsrcsrv { include!("../uapi/protocol/rsrcsrv.rs"); }

This page only documents the label numbers and roles. For the wire format of individual operations, see the server-specific documentation — docs/spec/ in the saltyos tree is the eventual landing place for that detail.

VFS server — vfs.rs

The VFS server owns the file descriptor table and every file-like object: regular files, directories, sockets, pipes, SHM objects, and poll/epoll sets.

Core file I/O

Label Operation

1 VFS_POSIX_OPEN

Open a path, return a file descriptor.

2 VFS_READ

Read from an fd into an inline IPC buffer region.

3 VFS_WRITE

Write an inline buffer to an fd.

4 VFS_CLOSE

Close an fd.

5 VFS_POSIX_STAT

stat(path) — fill a PosixStat struct.

6 VFS_LSEEK

Seek within an fd.

7 VFS_POSIX_FSTAT

fstat(fd) — stat via fd.

8 VFS_POSIX_ACCESS

Check access permissions on a path.

9 VFS_POSIX_UNLINK

Remove a file or directory entry.

10 VFS_POSIX_RENAME

Rename a path.

11 VFS_POSIX_MKDIR

Create a directory.

12 VFS_POSIX_RMDIR

Remove an empty directory.

13 VFS_POSIX_OPENDIR

Open a directory for enumeration.

14 VFS_POSIX_READDIR

Read the next directory entry.

15 VFS_POSIX_LSTAT

lstat(path) — stat without following a terminal symlink.

16 VFS_POSIX_POLL

Multiplex fd readiness.

17 VFS_POSIX_SHM_OPEN

shm_open(name) — open or create a POSIX shared memory object.

18 VFS_POSIX_SHM_UNLINK

shm_unlink(name).

19 VFS_POSIX_FTRUNCATE

Truncate an fd to a given size.

Sockets

Label Operation

20 VFS_POSIX_SOCKET

socket(domain, type, protocol).

21 VFS_POSIX_BIND

bind(fd, sockaddr, addrlen).

22 VFS_POSIX_LISTEN

listen(fd, backlog).

23 VFS_POSIX_ACCEPT

accept(fd, &addr, &addrlen).

24 VFS_POSIX_CONNECT

connect(fd, sockaddr, addrlen).

25 VFS_POSIX_SENDMSG

sendmsg(fd, msghdr, flags).

26 VFS_POSIX_RECVMSG

recvmsg(fd, msghdr, flags).

27 VFS_POSIX_SOCKPAIR

Create a socket pair.

28 VFS_POSIX_SHUTDOWN

Shut down one or both directions of a socket.

66 VFS_POSIX_GETSOCKNAME

Local address of a socket.

67 VFS_POSIX_GETPEERNAME

Remote address of a connected socket.

68 VFS_POSIX_SETSOCKOPT

Set a socket option.

69 VFS_POSIX_GETSOCKOPT

Get a socket option.

Pipes, descriptors, and fd table

Label Operation

29 VFS_POSIX_PIPE

Create an anonymous pipe pair.

30 VFS_POSIX_DUP

dup(oldfd).

31 VFS_POSIX_DUP2

dup2(oldfd, newfd).

32 VFS_POSIX_CLONE_FDS

Clone a subset of the fd table into a child CNode.

33 VFS_POSIX_IOCTL

Generic ioctl passthrough.

43 VFS_POSIX_DUP3

dup3(oldfd, newfd, flags) with O_CLOEXEC.

44 VFS_POSIX_MKFIFO

Create a named pipe.

Labels 34 and 35 were moved to protocol/posix.rs (as VFS_POSIX_ISATTY and VFS_POSIX_FCNTL) because they are POSIX personality-only operations — see posix.rs below. Labels 45 and 46 were removed when mmap ownership moved from VFS to mmsrv; the numbers are retired.

Directory and path operations

Label Operation

36 VFS_POSIX_CHDIR

chdir(path).

37 VFS_POSIX_GETCWD

getcwd().

38 VFS_POSIX_TCGETATTR

tcgetattr(fd) — TTY attributes read.

39 VFS_POSIX_TCSETATTR

tcsetattr(fd, …​) — TTY attributes write.

*at() family

Label Operation

47 VFS_POSIX_OPENAT

openat(dirfd, path, flags, mode).

48 VFS_POSIX_FSTATAT

fstatat(dirfd, path, &stat, at_flags).

49 VFS_POSIX_UNLINKAT

unlinkat(dirfd, path, at_flags).

50 VFS_POSIX_RENAMEAT

renameat(olddirfd, oldpath, newdirfd, newpath).

51 VFS_POSIX_MKDIRAT

mkdirat(dirfd, path, mode).

52 VFS_POSIX_FACCESSAT

faccessat(dirfd, path, mode, at_flags).

53 VFS_POSIX_FCHMODAT

fchmodat(dirfd, path, mode, at_flags).

54 VFS_POSIX_FCHOWNAT

fchownat(dirfd, path, uid, gid, at_flags).

55 VFS_POSIX_LINKAT

linkat(olddirfd, oldpath, newdirfd, newpath, flags).

56 VFS_POSIX_SYMLINKAT

symlinkat(target, dirfd, linkpath).

57 VFS_POSIX_READLINKAT

readlinkat(dirfd, path, &buf, bufsiz).

58 VFS_POSIX_UTIMENSAT

utimensat(dirfd, path, times, flags).

59 VFS_POSIX_FCHMOD

fchmod(fd, mode).

60 VFS_POSIX_FCHOWN

fchown(fd, uid, gid).

Epoll

Label Operation

40 VFS_POSIX_EPOLL_CREATE

Create an epoll fd.

41 VFS_POSIX_EPOLL_CTL

Add / modify / delete an epoll entry.

42 VFS_POSIX_EPOLL_WAIT

Wait for epoll events.

Bulk I/O, pagers, and administrative operations

Label Operation

61 VFS_CLIENT_EXIT

Client notifies VFS it is exiting so the fd table and poll sets can be reaped.

62 VFS_PREAD

Positional read.

63 VFS_PWRITE

Positional write.

64 VFS_BULK_SETUP

Prepare a shared-memory region for bulk I/O larger than the IPC register window.

65 VFS_BULK_READ

Bulk read into the shared region.

72 VFS_BULK_PWRITE

Bulk positional write.

70 VFS_BACKEND_PAGER_READ

Pager-side read: mmsrv asks VFS to fill a backing page.

71 VFS_BACKEND_PAGER_WRITE

Pager-side write-back.

73 VFS_BACKEND_RESOLVE_BACKING

Resolve an fd into a backing file / mount / device descriptor for mmsrv to page against.

75 VFS_DUMP_PENDING

Debug dump of pending VFS requests.

Multi-user, xattr, mount, and system operations

Label Operation

76 VFS_POSIX_STAT_FOR_EXEC

Stat + permission check used by exec() to validate the interpreter.

77 VFS_FSYNC

Flush file data to backing storage.

78 VFS_GETXATTR

Read an extended attribute.

79 VFS_SETXATTR

Write an extended attribute.

80 VFS_REMOVEXATTR

Remove an extended attribute.

81 VFS_LISTXATTR

List extended attribute names.

82 VFS_MOUNT

Mount a filesystem.

83 VFS_UMOUNT

Unmount a filesystem.

84 VFS_PIVOT_ROOT

pivot_root(new_root, put_old).

85 VFS_CLIENT_REGISTER

Personality registration — carries subsystem ID.

86 VFS_SYSCTL

Generic sysctl read/write.

87 VFS_POSIX_CANON_PATH

Canonicalize a path for exec().

88 VFS_WIN32_OPEN

Windows-shaped open carrying dwDesiredAccess, dwShareMode, dwCreationDisposition, dwFlagsAndAttributes. Used so VFS can perform proper share-mode arbitration without a lossy POSIX translation.

89 VFS_POSIX_UNSHARE

unshare(flags) — mount-namespace operations.

The VFS label space is by far the largest in trona and the one that changes most often as new POSIX and Win32 features land.

Process manager — procmgr.rs

procmgr owns process and thread lifecycle, signals, credentials, resource limits, and session/pgrp state.

Label Operation

1 PM_SPAWN

Spawn a new process from an ELF image.

2 PM_EXIT

Current process exits.

3 PM_WAIT

waitpid() — wait for a child.

4 PM_GETPID

Return the caller’s PID.

5 PM_FORK

Fork the current process (paired with fork.S trampoline).

6 PM_EXEC

execve() — replace the current process image.

7 PM_GETPPID

Return the parent PID.

8 PM_KILL

Send a signal to a process.

9 PM_SIGACTION

Install a signal handler.

10 PM_GETUID

Real user ID.

11 PM_GETGID

Real group ID.

12 PM_SETPGID

Set process group ID.

13 PM_GETPGID

Get process group ID of a process.

14 PM_SETSID

Create a new session and become session leader.

15 PM_GETEUID

Effective user ID.

16 PM_GETEGID

Effective group ID.

17 PM_GETGROUPS

Supplementary group list.

21 PM_REGISTER

Client registration — hands procmgr the client’s badge.

22 PM_GETSID

Get session ID of a process.

23 PM_GETPGID_BADGE

Get pgid of the badged caller itself.

24 PM_GETSID_BADGE

Get sid of the badged caller itself.

25 PM_KILL_PGID

Send a signal to an entire process group.

26 PM_INJECT_CAP

Give a capability to another running process (used by init during bootstrap).

27 PM_LIST_PIDS

Enumerate live PIDs.

28 PM_GET_PROC_INFO

Query per-process metadata (name, state, uid, …).

29 PM_RESUME

Resume a suspended process.

30 PM_UMASK

Read/write the umask.

32 PM_SETITIMER

Set an interval timer.

33 PM_GETITIMER

Read an interval timer.

34 PM_GET_EXE_PATH

Look up the executable path of a process.

35 PM_DUMP_PENDING

Debug dump of pending procmgr requests.

36 PM_GET_THREAD_CAPS

Get the TCB / SC / vspace caps of a thread.

Credentials

Label Operation

37 PM_SETUID

setuid(uid).

38 PM_SETGID

setgid(gid).

39 PM_SETEUID

seteuid(euid).

40 PM_SETEGID

setegid(egid).

41 PM_SETREUID

setreuid(ruid, euid).

42 PM_SETREGID

setregid(rgid, egid).

43 PM_SETGROUPS

Set supplementary groups.

44 PM_GET_CREDS_BY_BADGE

Look up credentials of a badged caller — used by VFS.

45 PM_GETRESUID

getresuid(&ruid, &euid, &suid).

46 PM_GETRESGID

getresgid(&rgid, &egid, &sgid).

47 PM_SETRESUID

setresuid(ruid, euid, suid).

48 PM_SETRESGID

setresgid(rgid, egid, sgid).

Limits, TTY, and providers

Label Operation

49 PM_GETRLIMIT

getrlimit(resource).

50 PM_SETRLIMIT

setrlimit(resource, rlim).

51 PM_SET_SESSION_TTY

Attach a controlling TTY to the current session.

52 PM_CLEAR_SESSION_TTY

Detach the controlling TTY.

53 PM_SET_SESSION_TTY_PGRP

Change the foreground process group of the controlling TTY.

54 PM_REGISTER_PERSONALITY_PROVIDER

Register a personality provider (e.g. posix_ttysrv).

Thread lifecycle (personality-agnostic)

Label Operation

55 PM_THREAD_CREATE

Create a new thread. Called by pthread_create and the future Win32 thread shim.

56 PM_THREAD_EXIT

Current thread exits.

57 PM_THREAD_JOIN

Wait for a thread to exit and collect its retval.

58 PM_THREAD_DETACH

Mark a thread as detached.

59 PM_THREAD_LIST

Enumerate threads in a process.

Boot-time init → procmgr handoff

Label Operation

60 PM_REGISTER_SERVICE_DEFS

Init ships the parsed .service definitions to procmgr as a single frame cap. Procmgr maps, validates magic+version, copies entries into a static registry, unmaps, and replies TRONA_OK.

61 PM_REGISTER_PROVIDER

Init registers a pre-procmgr service provider endpoint with procmgr so later Require=<name> lookups can resolve it.

Memory manager — mmsrv.rs

The memory manager owns heap break, mmap regions, SHM objects, COW pools, and page-fault backing resolution. Labels are allocated in the 0x80–0xA3 range, with a gap at 0x91 and several retired numbers.

Label Operation

0x80 MM_REGISTER

Client registration.

0x81 MM_DEREGISTER

Client teardown.

0x82 MM_BRK

Set the heap break.

0x83 MM_SBRK

Increment the heap break.

0x84 MM_MMAP

Anonymous mmap.

0x85 MM_MUNMAP

Unmap.

0x86 MM_MPROTECT

Change page protection flags.

0x87 MM_MAP_BATCH

Map multiple regions atomically.

0x88 MM_MAP_WINDOW

Allocate a reserved VA window.

0x89 MM_UNMAP_WINDOW

Release a reserved VA window.

0x8A MM_SHM_CREATE

Create a POSIX-style shared memory segment.

0x8B MM_SHM_MAP

Map an existing SHM segment.

0x8C MM_SHM_UNMAP

Unmap an SHM segment.

0x8D MM_FORK_REGIONS

Clone the caller’s mapped regions into a child vspace (used by posix_fork).

0x8E MM_SHM_DESTROY

Destroy an SHM segment.

0x8F MM_SHM_RESIZE

Resize an SHM segment.

0x90 MM_GET_CLIENT_STATS

Query per-client memory usage.

0x92 MM_REGISTER_SHARED_REGION

Register a region that will be shared with another client.

0x93 MM_MAP_OBJECT_REGION

Map a MemoryObject-backed region.

0x94 MM_SYNC_FILE_BACKING

Sync a file-backed mapping to VFS.

0x95 MM_FILE_MMAP

File-backed mmap. Delegates through VFS_BACKEND_RESOLVE_BACKING for fd → backing resolution.

0x97 MM_SYNC_MMAP_WRITE

Force write-back of a dirty file-backed mapping.

0x9A MM_PAGER_REQUEST

Pager client → mmsrv: please resolve a fault at this vaddr.

0x9B MM_PAGER_WRITE_REQUEST

Pager client → mmsrv: writeback request.

0x9C MM_DUMP_PENDING

Debug dump of pending mmsrv requests.

0x9D MM_REGISTER_PAGER_EP

Register a pager endpoint — used by drivers that provide page-fault handling for their own regions.

0x9E MM_ALLOC_PRIVATE_REGION

Allocate a private heap region.

0x9F MM_ALLOC_PRIVATE_WINDOW

Allocate a private VA window.

0xA0 MM_ALLOC_INITRD_COPY

Copy a range out of the initrd into a fresh mmsrv-owned frame.

0xA1 MM_ALLOC_BOOTINFO_COPY

Copy a range out of the bootinfo page.

0xA2 MM_COPY_FROM_CLIENT_REGION

Copy from one client’s region into another.

0xA3 MM_ALLOC_PRIVATE_COPY_FROM_CLIENT_REGION

Allocate private memory initialized from a client region.

Labels 0x91, 0x96, 0x98, 0x99 are reserved or retired:

  • 0x91 is the numeric gap between client stats (0x90) and the shared-region labels (0x92+).

  • 0x96 is reserved — device mmap is handled as a subcase of MM_FILE_MMAP.

  • 0x98 / 0x99 were MM_PROVISION_UNTYPED and MM_QUERY_CAPACITY from the era when mmsrv owned its own untyped pool; the numbers are retired but not reused.

Name service — namesrv.rs

namesrv is deliberately minimal: only two labels.

Label Operation

1 NS_REGISTER

Register a name → endpoint mapping.

2 NS_LOOKUP

Look up an endpoint by name.

The current name service is a flat dictionary used chiefly so that dns_resolve in trona_posix can find the dnssrv endpoint without having to hard-code a capability slot. More structured naming (directories, hierarchies) is planned but not yet landed.

POSIX personality — posix.rs

POSIX-only operations that are not part of the generic VFS protocol. These labels live in a separate file to make it clear that non-POSIX subsystems must not depend on them.

posix_ttysrv

Label Operation

1 POSIX_TTYSRV_GET_FG_PGRP

tcgetpgrp().

2 POSIX_TTYSRV_SET_FG_PGRP

tcsetpgrp().

3 POSIX_TTYSRV_SET_CTTY

Attach caller as the controlling TTY.

4 POSIX_TTYSRV_DROP_CTTY

Detach controlling TTY.

10 POSIX_TTYSRV_PTY_ALLOC

Allocate a new pty pair.

11 POSIX_TTYSRV_PTY_READ

Read from a pty slave.

12 POSIX_TTYSRV_PTY_WRITE

Write to a pty slave.

13 POSIX_TTYSRV_PTY_CLOSE

Close a pty endpoint.

14 POSIX_TTYSRV_PTY_TCGETATTR

Pty tcgetattr.

15 POSIX_TTYSRV_PTY_TCSETATTR

Pty tcsetattr.

16 POSIX_TTYSRV_PTY_IOCTL

Pty ioctl.

17 POSIX_TTYSRV_PTY_POLL

Pty poll.

18 POSIX_TTYSRV_INPUT_EVENT

Input event from the console driver.

19 POSIX_TTYSRV_PTY_COLLECT

Collect buffered data from a pty.

20 POSIX_TTYSRV_PTY_MASTER_WRITE

Write from the pty master side.

21 POSIX_TTYSRV_CLIENT_EXIT

Client teardown notification.

POSIX-only VFS labels

Labels 34 and 35 are VFS operations that were carved out of the generic VFS label space because they are POSIX personality-only:

Label Operation

34 VFS_POSIX_ISATTY

isatty(fd).

35 VFS_POSIX_FCNTL

fcntl(fd, cmd, arg).
The POSIX_TTYSRV_* constants in posix.rs duplicate the same names in server.rs. Both copies use the same numeric values. This redundancy is transitional and will be resolved when protocol/server.rs is reorganized.

Win32 personality — win32.rs

Labels used between PE binaries (via kernel32.dll or the yet-to-be-built trona_win32 Rust crate) and the win32_csrss server.

Label Operation

0x100 W32_RESOLVE_IMPORT

PE rtld import resolution. Wire: regs[0]=name_len, regs[1]=ordinal_hint, regs[2..]=name_bytes. Reply: regs[0]=kernel32_export_rva (0 = not found).

0x101 W32_CONSOLE_WRITE

Console write with inline data. Wire: regs[0]=byte_count, regs[1..]=data. Reply: regs[0]=bytes_written.

0x102 W32_CONSOLE_READ

Console read. Wire: regs[0]=max_bytes. Reply: regs[0]=actual_bytes, regs[1..]=data.

0x103 W32_GET_CONSOLE_MODE

Get mode flags for a console handle. Wire: regs[0]=console_handle_type (0=input, 1=output). Reply: regs[0]=mode_flags.

0x104 W32_SET_CONSOLE_MODE

Set mode flags. Wire: regs[0]=console_handle_type, regs[1]=mode_flags.

0x105 W32_CLIENT_REGISTER

PE process announces itself to csrss. Empty wire, TRONA_OK on success.

0x106 W32_CLIENT_EXIT

PE process is exiting. Wire: regs[0]=exit_code. Reply: TRONA_OK.

The win32.rs file also defines console mode flag constants that W32_GET_CONSOLE_MODE / W32_SET_CONSOLE_MODE exchange:

Bit Constant Meaning

0x0001

ENABLE_PROCESSED_INPUT

Input side — process Ctrl-C as SIGINT.

0x0002

ENABLE_LINE_INPUT

Input side — cook input line-by-line.

0x0004

ENABLE_ECHO_INPUT

Input side — echo typed characters.

0x0001

ENABLE_PROCESSED_OUTPUT

Output side — interpret escape sequences.

0x0002

ENABLE_WRAP_AT_EOL_OUTPUT

Output side — wrap lines at end of line.

Default modes are DEFAULT_INPUT_MODE = PROCESSED_INPUT | LINE_INPUT | ECHO_INPUT (0x0007) and DEFAULT_OUTPUT_MODE = PROCESSED_OUTPUT | WRAP_AT_EOL_OUTPUT (0x0003), matching the Windows defaults.

Of the seven Win32 labels, only W32_RESOLVE_IMPORT (via the PE rtld import resolver), W32_CLIENT_REGISTER (via the future crt startup), and W32_CLIENT_EXIT (via ExitProcess) are expected to be wired in the current PE pipeline. The four W32_CONSOLE_* labels are defined in the UAPI but are not used by any code built today — kernel32.dll’s `WriteConsoleA/ReadConsoleA implementations go through VFS directly, and the trona_win32 Rust crate that would have called these labels is not built by any meson target. See trona_win32 Overview for the full story.

Server and driver — server.rs

A catch-all file for labels used between servers and drivers that do not fit elsewhere.

Console server

Label Operation

1 CONSOLE_WRITE

Write bytes to the console.

2 CONSOLE_READ

Read bytes from the console.

3 CONSOLE_TCGETATTR

Console termios query.

4 CONSOLE_TCSETATTR

Console termios update.

posix_ttysrv (duplicate of posix.rs)

The same 15 POSIX_TTYSRV_* labels from protocol/posix.rs are re-declared here with the same values (1–4, 10–21). Call sites historically included this file before the split; the duplication is transitional.

Display server

Label Operation

1 DISPLAY_GET_INFO

Query display metrics.

2 DISPLAY_PRESENT

Present a framebuffer update.

6 DISPLAY_FILL_RECT

Fill a rectangle.

7 DISPLAY_WRITE_TEXT

Write text at given coordinates.

8 DISPLAY_TERMINAL_WRITE

Write to the terminal subregion.

9 DISPLAY_SETUP_RING

Set up a command ring buffer for async drawing.

PCI enumeration server

Label Operation

1 PCI_FIND_DEVICE

Look up a PCI device by vendor:device.

2 PCI_GET_CAPS

Enumerate the device’s capability list.

3 PCI_LIST

List every enumerated device.

4 PCI_READ_CONFIG32

Read a 32-bit config space register.

5 PCI_GET_BAR_CAP

Return a cap to a BAR range.

6 PCI_WRITE_CONFIG32

Write a 32-bit config space register.

Block device driver

Label Operation

1 BLK_READ

Read sectors.

2 BLK_WRITE

Write sectors.

3 BLK_GET_INFO

Device geometry query.

4 BLK_FLUSH

Flush caches.

5 BLK_GET_SHM_ID

Return the SHM descriptor used for bulk transfer.

SaltyFS server

Label Operation

1 SALTYFS_MOUNT

Mount a SaltyFS image.

2 SALTYFS_LOOKUP

Lookup a name in a directory.

3 SALTYFS_READ

Read a file.

4 SALTYFS_READDIR

Enumerate a directory.

5 SALTYFS_STAT

Stat a file.

6 SALTYFS_GETINFO

Volume-level info.

7 SALTYFS_READ_INLINE

Read a small file inline via IPC registers.

8 SALTYFS_WRITE_INLINE

Write inline.

9 SALTYFS_CREATE

Create a file.

10 SALTYFS_MKDIR

Create a directory.

11 SALTYFS_UNLINK

Remove a file.

12 SALTYFS_RMDIR

Remove an empty directory.

13 SALTYFS_RENAME

Rename.

14 SALTYFS_TRUNCATE

Truncate a file.

15 SALTYFS_SHM_SETUP

Set up bulk transfer SHM.

16 SALTYFS_WRITE

Bulk write.

17 SALTYFS_SYMLINK

Create a symlink.

18 SALTYFS_READLINK

Read a symlink target.

19 SALTYFS_LINK

Hard link.

20 SALTYFS_GETPARENT

Get the parent inode.

21 SALTYFS_CHMOD

Change mode bits.

22 SALTYFS_CHOWN

Change owner.

23 SALTYFS_GETXATTR

Get extended attribute.

24 SALTYFS_SETXATTR

Set extended attribute.

25 SALTYFS_REMOVEXATTR

Remove xattr.

26 SALTYFS_LISTXATTR

List xattrs.

Network stack (netsrv)

Label Operation

0xA0 NET_SOCKET

Create a socket.

0xA1 NET_CONNECT

Connect.

0xA2 NET_SEND

Send.

0xA3 NET_RECV

Receive.

0xA4 NET_CLOSE

Close.

0xA5 NET_BIND

Bind.

0xA6 NET_LISTEN

Listen.

0xA7 NET_ACCEPT

Accept.

0xA8 NET_SENDTO

Sendto.

0xA9 NET_RECVFROM

Recvfrom.

0xAA NET_SHUTDOWN

Shutdown.

0xAB NET_GETSOCKNAME

Get local address.

0xAC NET_GETPEERNAME

Get peer address.

0xAD NET_SETSOCKOPT

Set option.

0xAE NET_GETSOCKOPT

Get option.

0xAF NET_POLL_STATUS

Readiness query.

0xB0 NET_REGISTER_VFS

Register a VFS as a netsrv client.

0xB1 NET_COMPLETE

Completion notification for a deferred operation.

0xB2 NET_DNS_RESOLVE

DNS A/AAAA lookup.

0xB3 NET_DNS_RESOLVE_PTR

DNS PTR lookup.

0xB4 NET_GET_CONFIG

Read network config.

0xB5 NET_GET_ARP_ENTRY

Look up an ARP entry.

0xB6 NET_RECV_WAIT

Split blocking primitive for recv.

0xB7 NET_ACCEPT_WAIT

Split blocking primitive for accept.

0xB8 NET_RECVFROM_WAIT

Split blocking primitive for recvfrom.

0xB9 NET_SEND_WAIT

Split blocking primitive for send.

0xBA NET_SENDTO_WAIT

Split blocking primitive for sendto.

DNS service

Label Operation

1 DNS_RESOLVE

Forward DNS lookup.

2 DNS_CACHE_FLUSH

Clear the local cache.

3 DNS_REVERSE_LOOKUP

Reverse lookup.

Driver registration

Label Operation

0xC0 DRIVER_REGISTER

Driver ↔ parent server registration.

0xC1 DRIVER_GET_INFO

Query driver metadata.

Resource server — rsrcsrv.rs

rsrcsrv is the runtime authority for kernel object allocation, quota accounting, and owner-based reclaim. Labels live in the 0xE0–0xE6 range.

Label Operation

0xE0 RES_ALLOC_OBJECT

Allocate a single kernel object. Request: MR0=owner_id, MR1=obj_type, MR2=size_bits, MR3=flags. Reply carries the new cap in caps[0], the handle in MR0, and status in MR1.

0xE1 RES_ALLOC_BATCH

Allocate a heterogeneous batch in one IPC. Up to 8 entries inline via MRs; larger batches use the IPC buffer.

0xE2 RES_FREE_HANDLE

Free a handle previously returned by RES_ALLOC_OBJECT / RES_ALLOC_BATCH. rsrcsrv revokes the back-reference cap (invalidating every derived cap) and decrements quota.

0xE3 RES_RECLAIM_OWNER

Reclaim every handle owned by a given owner_id. Used on process exit.

0xE4 RES_QUERY_USAGE

Query current quota usage — bytes in use and handle count.

0xE5 RES_SET_QUOTA

Set or update quota limits. Setting both to 0 means unlimited. The high bit of MR2 (RES_QUOTA_FLAG_PROMOTE_PRIVILEGED = 1 << 63) is reserved for init to promote a target owner_id (typically procmgr) into the privileged caller set so it can allocate on behalf of other owners.

0xE6 RES_ADOPT_UNTYPED

Hand an untyped capability to rsrcsrv’s pool. Used by init during boot to transfer all root untypeds after spawning rsrcsrv.

RES_QUOTA_FLAG_PROMOTE_PRIVILEGED is a flag used inside the RES_SET_QUOTA request, not a standalone label.

Related pages

  • Syscall ABI — the SYS_CALL / SYS_SEND syscalls that carry these labels.

  • Invoke Labels — kernel capability invocation labels (distinct from IPC protocol labels).

  • Error Codes — the error space returned in replies to these calls.

  • trona_posix Overview — the client-side code that builds most of these messages.