Stdlib module kernel/signals.vitl
This page is a wiki-style reference for one concrete stdlib file. It explains what the file owns, where it fits in the family, and how to decide whether this is the right surface to depend on.
kernel/signals.vitl.Family: kernel
Kind: public stdlib surface
Page style: this reference follows the same “encyclopedic card + portrait + usage contract” logic as the keyword pages, but for stdlib modules.
Summary
- Overview
- Purpose
- Taxonomy
- Implementation profile
- Top-level API inventory
- Position in family
- Declaration map
- Representative signatures
- How to use this module
- User example
- Keyword coverage
- Source shape
- Source landmarks
- Source organization
- Complete API catalog
- Integration boundaries
- Composition guidance
- Relationship table
- Neighbor modules
Overview
| Field | Value |
|---|---|
| Path | kernel/signals.vitl |
| Family | kernel |
| Kind | public stdlib surface |
| Line count | 151 |
| Declared procedures | 18 |
| Declared forms/picks | 1 |
`kernel/signals.vitl` is a public stdlib surface inside the `kernel` family. It should be read as one focused slice of the broader family responsibility: System-facing runtime helpers such as process, scheduler, threads, sync, users, signals, network, device, and memory.
Purpose
This file should be chosen because of responsibility, not because its name “sounds close enough”. Inside the kernel family, it carries one focused part of the contract and keeps that responsibility separate from neighboring concerns.
- A service manager may use scheduler, process, and signals while keeping policy in separate code.
- A network-facing runtime should explain why it depends on kernel surfaces instead of lighter families.
Taxonomy
Think of this page as a generated encyclopedia entry rather than a hand-written tutorial. The goal is to show what kind of module this is, how dense it is, and what reading strategy makes sense before depending on it.
- Medium procedure surface: this file groups several related operations behind one namespace.
- Owns domain vocabulary: the module declares data shapes in addition to executable helpers, so its types are part of the contract.
- Has tuning constants: part of the module behavior is controlled by named constants that document default precision, limits, or policy.
- Minimal top-level dependencies: the module reads as mostly self-contained from its opening declarations.
Implementation profile
This profile is inferred directly from the source text. It does not replace reading the file, but it tells you quickly whether the module is mostly declarative, loop-heavy, branch-heavy, or organized around many small exits.
| Signal | Count | What it suggests |
|---|---|---|
if | 0 | Branching density and local decision-making. |
while | 0 | Loop-heavy or iterative implementation style. |
for | 0 | Collection-style traversal at source level. |
match | 0 | Variant-driven branching or grammar-style decoding. |
let | 0 | Local state and intermediate value density. |
give | 18 | Number of explicit exit points and result shaping. |
Top-level API inventory
| Surface | Items |
|---|---|
| Procedures | signal, signal_default, signal_ignore, sigaction, sigprocmask, pthread_sigmask, kill, raise, alarm, pause, sigsuspend, sigpending |
| Forms | SignalSet |
| Picks | none declared at top level |
| Constants | SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGTRAP, SIGABRT, SIGBUS, SIGFPE, SIGKILL, SIGUSR1, SIGSEGV, SIGUSR2 |
| Exports | none declared at top level |
Imported surfaces
This file does not advertise a top-level `use` surface in its opening declarations. That often means it is either self-contained or an aggregation layer.
Position in family
This file is module 9 of 12 in the kernel family when ordered by path. By procedure count it ranks 6, and by line count it ranks 6. Those ranks are useful as rough signals of breadth, not as quality judgments.
Declaration map
The declaration map turns raw source into a scan-friendly catalog. It is useful when the file is large enough that a reader wants to orient by kinds of surfaces first.
| Line | Name | Kind | Role |
|---|---|---|---|
| 1 | vitte/stdlib_checked/kernel_signals | space | Declares the namespace that anchors this file in the stdlib tree. |
| 9 | SIGHUP | const | Defines a named constant reused across the module. |
| 11 | SIGINT | const | Defines a named constant reused across the module. |
| 13 | SIGQUIT | const | Defines a named constant reused across the module. |
| 15 | SIGILL | const | Defines a named constant reused across the module. |
| 17 | SIGTRAP | const | Defines a named constant reused across the module. |
| 19 | SIGABRT | const | Defines a named constant reused across the module. |
| 21 | SIGBUS | const | Defines a named constant reused across the module. |
| 23 | SIGFPE | const | Defines a named constant reused across the module. |
| 25 | SIGKILL | const | Defines a named constant reused across the module. |
| 27 | SIGUSR1 | const | Defines a named constant reused across the module. |
| 29 | SIGSEGV | const | Defines a named constant reused across the module. |
| 31 | SIGUSR2 | const | Defines a named constant reused across the module. |
| 33 | SIGPIPE | const | Defines a named constant reused across the module. |
| 35 | SIGALRM | const | Defines a named constant reused across the module. |
| 37 | SIGTERM | const | Defines a named constant reused across the module. |
| 39 | SIGCHLD | const | Defines a named constant reused across the module. |
| 41 | SIGCONT | const | Defines a named constant reused across the module. |
| 43 | SIGSTOP | const | Defines a named constant reused across the module. |
| 45 | SIGTSTP | const | Defines a named constant reused across the module. |
| 47 | SIGTTIN | const | Defines a named constant reused across the module. |
| 49 | SIGTTOU | const | Defines a named constant reused across the module. |
| 51 | SIGPOLL | const | Defines a named constant reused across the module. |
| 53 | SIGPROF | const | Defines a named constant reused across the module. |
| 55 | SIGSYS | const | Defines a named constant reused across the module. |
| 57 | SA_NOCLDSTOP | const | Defines a named constant reused across the module. |
| 59 | SA_NOCLDWAIT | const | Defines a named constant reused across the module. |
| 61 | SA_NODEFER | const | Defines a named constant reused across the module. |
| 63 | SA_ONSTACK | const | Defines a named constant reused across the module. |
| 65 | SA_RESETHAND | const | Defines a named constant reused across the module. |
| 67 | SA_RESTART | const | Defines a named constant reused across the module. |
| 69 | SA_SIGINFO | const | Defines a named constant reused across the module. |
| 71 | SIG_BLOCK | const | Defines a named constant reused across the module. |
| 73 | SIG_UNBLOCK | const | Defines a named constant reused across the module. |
| 75 | SIG_SETMASK | const | Defines a named constant reused across the module. |
| 77 | SignalSet | form | Introduces a structured data shape that other procedures can exchange. |
| 81 | signal | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 85 | signal_default | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 89 | signal_ignore | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 93 | sigaction | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 97 | sigprocmask | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 101 | pthread_sigmask | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 105 | kill | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 109 | raise | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 113 | alarm | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 117 | pause | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 121 | sigsuspend | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 125 | sigpending | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 129 | sigwait | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 133 | sigemptyset | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 137 | sigfillset | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 141 | sigaddset | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 145 | sigdelset | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 149 | sigismember | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
The table is exhaustive for top-level declarations of the selected kinds. This file declares 54 matching surfaces.
Representative signatures
These signatures are shown in source order so the page keeps the feel of a reference manual, not just a keyword cloud.
const SIGHUP: int = 0(line 9)const SIGINT: int = 0(line 11)const SIGQUIT: int = 0(line 13)const SIGILL: int = 0(line 15)const SIGTRAP: int = 0(line 17)const SIGABRT: int = 0(line 19)const SIGBUS: int = 0(line 21)const SIGFPE: int = 0(line 23)const SIGKILL: int = 0(line 25)const SIGUSR1: int = 0(line 27)const SIGSEGV: int = 0(line 29)const SIGUSR2: int = 0(line 31)const SIGPIPE: int = 0(line 33)const SIGALRM: int = 0(line 35)const SIGTERM: int = 0(line 37)const SIGCHLD: int = 0(line 39)const SIGCONT: int = 0(line 41)const SIGSTOP: int = 0(line 43)
The list is intentionally capped here; the source file declares 53 matching signatures in total.
How to use this module
Start by reading the file as an ownership boundary. Ask three questions: what enters this module, what stable types or procedures it exports, and what adjacent module should stay outside of it.
- Read
spaceand top-level imports first so the ownership boundary ofkernel/signals.vitlis explicit. - Scan constants before procedures; they often encode precision, limits, or policy assumptions that explain later behavior.
- Read declared forms and picks before algorithms so the data vocabulary is stable in your head.
- Traverse procedures in source order; the early helpers usually explain the naming and numeric conventions used later.
- Only after that compare neighbor modules, because the right boundary choice matters more than memorizing one helper name.
User example
This example is generated from the actual stdlib module surface. Its job is not to be the smallest snippet possible; its job is to show a realistic consumer-shaped file that exercises the module and mirrors the language keywords the module itself relies on.
space demo/kernel_signals
const SAMPLE_LABEL: string = "demo"
form UserReport {
label: string,
ready: bool
}
proc run_example() -> UserReport {
give UserReport { label: "ok", ready: ready }
}
Keyword coverage
This table makes the “all keywords of the module” requirement auditable. It compares the detected Vitte keywords in the source file with the generated consumer example above.
| Keyword | Present in module source | Used in generated user example |
|---|---|---|
space | yes | yes |
const | yes | yes |
form | yes | yes |
proc | yes | yes |
give | yes | yes |
The generated snippet exercises every detected Vitte keyword used by this module.
Source shape
space vitte/stdlib_checked/kernel_signals
const SIGHUP: int = 0
const SIGINT: int = 0
const SIGQUIT: int = 0
const SIGILL: int = 0
const SIGTRAP: int = 0
const SIGABRT: int = 0
const SIGBUS: int = 0
const SIGFPE: int = 0
const SIGKILL: int = 0
The excerpt is not meant to replace the file. It exists to make the module recognizable at first glance, the same way a Wikipedia infobox helps the reader orient before reading the whole article.
Source landmarks
Large files are easier to retain when they have visible landmarks. When the source contains explicit section banners, they are surfaced here; otherwise the first major declarations are used as anchors.
- Line 1:
space vitte/stdlib_checked/kernel_signals - Line 9:
const SIGHUP: int = 0 - Line 11:
const SIGINT: int = 0 - Line 13:
const SIGQUIT: int = 0 - Line 15:
const SIGILL: int = 0 - Line 17:
const SIGTRAP: int = 0 - Line 19:
const SIGABRT: int = 0 - Line 21:
const SIGBUS: int = 0
Source organization
When a file carries its own internal chaptering, those chapters usually reveal the intended reading order better than a flat symbol list. This section reconstructs that organization from the source itself.
File surfaces
Top-level items: 54. Procedures: 18. Data surfaces: 1. Constants: 34.
First visible names: vitte/stdlib_checked/kernel_signals, SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGTRAP, SIGABRT, SIGBUS, SIGFPE, SIGKILL
Complete API catalog
This catalog is the exhaustive file-level index for the module. It is intentionally closer to a generated encyclopedia appendix than to a tutorial summary.
Constants
| Line | Name | Signature | Role |
|---|---|---|---|
| 9 | SIGHUP | const SIGHUP: int = 0 | Defines a named constant reused across the module. |
| 11 | SIGINT | const SIGINT: int = 0 | Defines a named constant reused across the module. |
| 13 | SIGQUIT | const SIGQUIT: int = 0 | Defines a named constant reused across the module. |
| 15 | SIGILL | const SIGILL: int = 0 | Defines a named constant reused across the module. |
| 17 | SIGTRAP | const SIGTRAP: int = 0 | Defines a named constant reused across the module. |
| 19 | SIGABRT | const SIGABRT: int = 0 | Defines a named constant reused across the module. |
| 21 | SIGBUS | const SIGBUS: int = 0 | Defines a named constant reused across the module. |
| 23 | SIGFPE | const SIGFPE: int = 0 | Defines a named constant reused across the module. |
| 25 | SIGKILL | const SIGKILL: int = 0 | Defines a named constant reused across the module. |
| 27 | SIGUSR1 | const SIGUSR1: int = 0 | Defines a named constant reused across the module. |
| 29 | SIGSEGV | const SIGSEGV: int = 0 | Defines a named constant reused across the module. |
| 31 | SIGUSR2 | const SIGUSR2: int = 0 | Defines a named constant reused across the module. |
| 33 | SIGPIPE | const SIGPIPE: int = 0 | Defines a named constant reused across the module. |
| 35 | SIGALRM | const SIGALRM: int = 0 | Defines a named constant reused across the module. |
| 37 | SIGTERM | const SIGTERM: int = 0 | Defines a named constant reused across the module. |
| 39 | SIGCHLD | const SIGCHLD: int = 0 | Defines a named constant reused across the module. |
| 41 | SIGCONT | const SIGCONT: int = 0 | Defines a named constant reused across the module. |
| 43 | SIGSTOP | const SIGSTOP: int = 0 | Defines a named constant reused across the module. |
| 45 | SIGTSTP | const SIGTSTP: int = 0 | Defines a named constant reused across the module. |
| 47 | SIGTTIN | const SIGTTIN: int = 0 | Defines a named constant reused across the module. |
| 49 | SIGTTOU | const SIGTTOU: int = 0 | Defines a named constant reused across the module. |
| 51 | SIGPOLL | const SIGPOLL: int = 0 | Defines a named constant reused across the module. |
| 53 | SIGPROF | const SIGPROF: int = 0 | Defines a named constant reused across the module. |
| 55 | SIGSYS | const SIGSYS: int = 0 | Defines a named constant reused across the module. |
| 57 | SA_NOCLDSTOP | const SA_NOCLDSTOP: i32 = 0 | Defines a named constant reused across the module. |
| 59 | SA_NOCLDWAIT | const SA_NOCLDWAIT: i32 = 0 | Defines a named constant reused across the module. |
| 61 | SA_NODEFER | const SA_NODEFER: i32 = 0 | Defines a named constant reused across the module. |
| 63 | SA_ONSTACK | const SA_ONSTACK: i32 = 0 | Defines a named constant reused across the module. |
| 65 | SA_RESETHAND | const SA_RESETHAND: i32 = 0 | Defines a named constant reused across the module. |
| 67 | SA_RESTART | const SA_RESTART: i32 = 0 | Defines a named constant reused across the module. |
| 69 | SA_SIGINFO | const SA_SIGINFO: i32 = 0 | Defines a named constant reused across the module. |
| 71 | SIG_BLOCK | const SIG_BLOCK: int = 0 | Defines a named constant reused across the module. |
| 73 | SIG_UNBLOCK | const SIG_UNBLOCK: int = 0 | Defines a named constant reused across the module. |
| 75 | SIG_SETMASK | const SIG_SETMASK: int = 0 | Defines a named constant reused across the module. |
Data surfaces
| Line | Name | Signature | Role |
|---|---|---|---|
| 77 | SignalSet | form SignalSet { | Introduces a structured data shape that other procedures can exchange. |
Procedures
| Line | Name | Signature | Role |
|---|---|---|---|
| 81 | signal | proc signal() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 85 | signal_default | proc signal_default() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 89 | signal_ignore | proc signal_ignore() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 93 | sigaction | proc sigaction() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 97 | sigprocmask | proc sigprocmask() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 101 | pthread_sigmask | proc pthread_sigmask() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 105 | kill | proc kill() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 109 | raise | proc raise() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 113 | alarm | proc alarm() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 117 | pause | proc pause() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 121 | sigsuspend | proc sigsuspend() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 125 | sigpending | proc sigpending() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 129 | sigwait | proc sigwait() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 133 | sigemptyset | proc sigemptyset() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 137 | sigfillset | proc sigfillset() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 141 | sigaddset | proc sigaddset() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 145 | sigdelset | proc sigdelset() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 149 | sigismember | proc sigismember() -> int { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
Integration boundaries
Within kernel, this file should remain focused. If a future helper changes the host boundary, scheduling boundary, or data-shape boundary, it probably belongs in a neighbor module instead of being added here by convenience.
- Family responsibility: System-facing runtime helpers such as process, scheduler, threads, sync, users, signals, network, device, and memory.
- Family architecture role: Use `kernel` when the program explicitly models system services, scheduling, process behavior, or device-facing coordination.
Composition guidance
Choose this module when
- Choose
kernel/signals.vitlwhen the main question is owned by this module rather than by transport, storage, orchestration, or user-interface code. - A service manager may use scheduler, process, and signals while keeping policy in separate code.
- A network-facing runtime should explain why it depends on kernel surfaces instead of lighter families.
Pause before extending it when
- Avoid extending this file when the new helper mostly changes the boundary to host I/O, runtime coordination, or foreign integration instead of staying inside
kernel. - Check nearby modules such as
kernel/device.vitl,kernel/fileio.vitl,kernel/interrupt.vitlbefore adding convenience wrappers here.
Relationship table
This table keeps the page closer to a real encyclopedia entry: a module is easier to understand when compared with its nearest alternatives in the same family.
| Neighbor | Procedures | Data surfaces | Why compare it |
|---|---|---|---|
kernel/device.vitl | 0 | 0 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/fileio.vitl | 44 | 2 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/interrupt.vitl | 9 | 0 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/memory.vitl | 18 | 1 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/network.vitl | 42 | 4 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/process.vitl | 14 | 2 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/scheduler.vitl | 1 | 0 | Shares the same family boundary but carries a distinct slice of responsibility. |
kernel/sync.vitl | 34 | 6 | Shares the same family boundary but carries a distinct slice of responsibility. |