---
name: "syd-sys"
section: "1"
platform: "linux"
package: "syd"
version: "3.59.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/syd-sys"
---

# syd-sys(1)

Lookup syscalls, errnos, ioctls, open flags, and signals by number or regular expression

## NAME

**syd-sys** - Lookup syscalls, errnos, ioctls, open flags, and signals by number or regular expression

## SYNOPSIS

**syd-sys** *\[-heios\]* *\[-a arch\]* *number\|regex*

**syd-sys** *-a list*

**syd-sys** *\[-uU\]*

## DESCRIPTION

Given a number, **syd-sys** prints the matching syscall name.

Given a regex, **syd-sys** prints case-insensitively matching syscall names.

Use **-e** to query [*errno*(3)](/errno/3.md) numbers.

Use **-i** to query [*ioctl*(2)](/ioctl/2.md) requests.

Use **-o** to query [*open*(2)](/open/2.md) flags.

Use **-s** to query [*signal*(7)](/signal/7.md) numbers.

Use **-u** to list UNIX domain socket inodes and names using [*netlink*(7)](/netlink/7.md).

Use **-U** to list UNIX domain socket inodes and names using [*proc\_net*(5)](/proc_net/5.md).

For both **-u** and **-U**, each line is the inode and name separated by a tab. Abstract sockets are prefixed with **@** and unnamed sockets are displayed as **!unnamed**.

## OPTIONS

| | |
| --- | --- |
| **-h** | Display help. |
| **-a** | Specify alternative architecture, such as **x86**, **x86\_64** and **aarch64**. |
|  | Use **list** to print the list of libseccomp supported architectures. |
| **-e** | Query [*errno*(3)](/errno/3.md) numbers. |
| **-i** | Query [*ioctl*(2)](/ioctl/2.md) requests. |
| **-o** | Query [*open*(2)](/open/2.md) flags. |
| **-s** | Query [*signal*(7)](/signal/7.md) numbers. |
| **-u** | List UNIX domain socket inodes and names using [*netlink*(7)](/netlink/7.md). |
| **-U** | List UNIX domain socket inodes and names using [*proc\_net*(5)](/proc_net/5.md). |

## SEE ALSO

[*syd*(1)](/syd/1.md), [*syd*(2)](/syd/2.md), [*syd*(5)](/syd/5.md), [*errno*(3)](/errno/3.md), [*ioctl*(2)](/ioctl/2.md), [*open*(2)](/open/2.md), [*syscall*(2)](/syscall/2.md), [*signal*(7)](/signal/7.md), [*netlink*(7)](/netlink/7.md)

**syd** homepage: https://sydbox.exherbo.org/

## AUTHORS

Maintained by Ali Polatel. Up-to-date sources can be found at https://gitlab.exherbo.org/sydbox/sydbox.git and on Radicle at rad:z38HCnbmcDegA2BMxuPaPRPMdp6wF. Bugs/patches can be submitted to https://gitlab.exherbo.org/groups/sydbox/-/issues. Discuss in #sydbox on Libera Chat or in #sydbox:mailstation.de on Matrix.