attr_multif - Linux

Overview

attr_multif is a command-line tool used to set or retrieve multiple extended attributes simultaneously for a file or directory. It allows efficient handling of extended attributes, particularly for tasks involving multiple attributes.

Syntax

attr_multif [-h] [-V] [-v] [-Z] [-c CHAR] [-p PATH] [-f PATH] [-m METHOD] ATTRS

Options/Flags

  • -h, –help: Display help message and exit.
  • -V, –version: Display version information and exit.
  • -v, –verbose: Enable verbose output.
  • -Z, –null: Terminate output with a null character.
  • -c CHAR, –delim=CHAR: Specify delimiter to separate attributes in output. Default: newline.
  • -p PATH, –preprocess=PATH: Specify a script for attribute value preprocessing.
  • -f PATH, –file=PATH: Read attribute names from a file.
  • -m METHOD, –method=METHOD: Set attribute value using the specified method. Default: set. Valid methods include: set, create, replace, append, delete, dump, path, env.

Examples

Set multiple attributes for a file:

attr_multif -m set user.name "John Doe" user.email "john.doe@example.com" file.type "document" sample.txt

Retrieve multiple attributes from a file:

attr_multif sample.txt user.name user.email

Dump attribute values to a file:

attr_multif -m dump sample.txt user.name user.email > attributes.txt

Common Issues

Error: "No such attribute": The specified attribute does not exist for the given file.
Solution: Verify the attribute name or create the attribute before setting its value.

Error: "Permission denied": The user does not have sufficient permissions to modify the attributes.
Solution: Ensure the user has write permissions for the file and any necessary directories.

Integration

Attr_multif can be combined with other Linux commands for advanced tasks, such as:

  • Use awk to filter or manipulate attribute values:
attr_multif -m dump sample.txt | awk -F ':' '{print $1}'
  • Use xargs to apply attr_multif to multiple files:
find . -name "*.txt" -print0 | xargs -0 attr_multif -m set user.created "$(date +%Y-%m-%d)"

Related Commands

  • setfattr: Set extended attributes for a file.
  • getfattr: Retrieve extended attributes for a file.
  • gnulib: Project providing a collection of libraries and tools, including attr_multif.