fuser

name	fuser
description	Use this skill when the user needs to identify processes using files, sockets, or filesystems.

fuser Plugin

Identify processes using files, sockets, or filesystems. Essential for debugging file locking, port conflicts, and resource contention issues.

Commands

File & Socket Inspection

• fuser file check <path> — Identify processes using a file or socket
• fuser tcp port <port> — Find processes using a specific TCP port
• fuser self version — Show fuser version info
• fuser _ _ <args> — Passthrough to fuser CLI

Usage Examples

• "Check what process is using file /var/log/syslog"
• "Find which process is using port 8080"
• "Kill all processes using /dev/ttyUSB0"

Installation

# Pre-installed on most Linux systems
# If missing:
apt-get install util-linux
supercli plugins install ./plugins/fuser --on-conflict replace --json

Examples

# Check what process is using a file
fuser -v /var/log/syslog

# Find processes using TCP port 8080
fuser -v 8080/tcp

# Kill processes using a file
fuser -k /path/to/file

# Find processes on a mount point
fuser -vm /mnt/data

# List processes using IPC resources
fuser -v --ipc /dev/shm/some-file

Key Features

• Identify PIDs using files, sockets, and filesystems
• Kill processes blocking resources
• TCP/UDP port conflict resolution
• Mount point usage inspection
• IPC resource tracking