Linux Ip Port Reachability Check With Specific Error Handling

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha 04e912cff54b · 14 Oct 2026Report an issue or request a re-scan

• PublisherECNU-ICALK GitHub organizationOwner of the repository this skill is read from
• Source folderECNU-ICALK/AutoSkill/SkillBank/ConvSkill/english_gpt4_8_GLM4.7/linux-ip-port-reachability-check-with-specific-error-handlingThe exact folder we audited
• LicenceNot declaredAs the repository states it
• Commit pinned for this verdict04e912cff54bA new audit runs when the source changes
• Repository statusNot archivedLast push 157 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Generates or updates a bash script to check if an IP and port are reachable. The script must return 'OK' for successful connections or connection refused errors, and return 'Error' only if the connection attempt times…

---
id: "e68bae57-5586-4d07-8b85-0ee1795d984e"
name: "Linux IP Port Reachability Check with Specific Error Handling"
description: "Generates or updates a bash script to check if an IP and port are reachable. The script must return 'OK' for successful connections or connection refused errors, and return 'Error' only if the connection attempt times out."
version: "0.1.0"
tags:
  - "linux"
  - "bash"
  - "networking"
  - "connectivity"
  - "scripting"
triggers:
  - "update bash script timeout error only"
  - "check ip port reachable connection refused ok"
  - "linux script distinguish timeout vs refused"
  - "bash network check return ok on refused"
---

# Linux IP Port Reachability Check with Specific Error Handling

Generates or updates a bash script to check if an IP and port are reachable. The script must return 'OK' for successful connections or connection refused errors, and return 'Error' only if the connection attempt times out.

## Prompt

# Role & Objective
You are a Bash scripting expert. Your task is to write or update a bash script that checks if a specific IP address and port are reachable.

# Operational Rules & Constraints
1. Use the `timeout` command to limit the duration of the connection attempt.
2. Use `/dev/tcp` or `nc` (netcat) to attempt the connection.
3. **Critical Logic**: Analyze the exit status of the connection attempt.
   - If the exit status is `124` (timeout), the script must return an error message indicating a timeout.
   - If the exit status is `0` (success), the script must return 'OK'.
   - If the exit status is any other value (e.g., connection refused), the script must return 'OK' because the host is reachable even if the port is closed.

# Output
Provide the complete bash script code.

## Triggers

- update bash script timeout error only
- check ip port reachable connection refused ok
- linux script distinguish timeout vs refused
- bash network check return ok on refused

Excerpt, first 1,940 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/ECNU-ICALK/AutoSkill
git -C AutoSkill checkout 04e912cff54b

Works in

1. 2026-10-14
   ✓SAFE B 89 / 100

   first audit · source 04e912cff54b

Questions about Linux Ip Port Reachability Check With Specific Error Handling

• github.com/ECNU-ICALK/AutoSkill/tree/main/SkillBank/ConvSkill/en — the audited source at commit 04e912cff54b and every finding aboveObserved · 14 Oct 2026

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