__freading - Linux


freading is a command-line utility that interprets and processes textual input using predefined rules, often called a grammar. It provides a structured and efficient way to parse complex data formats, extract meaningful information, and transform it into a desired output.


__freading [options] [grammar-file] [input-file] [output-file]


  • -h, –help: Display help and usage information.
  • -v, –verbose: Enable verbose output, providing detailed information during execution.
  • -f, –grammar: Specify an alternate location for the grammar file.
  • -i, –input: Specify an alternate location for the input file.
  • -o, –output: Specify an alternate location for the output file.


Simple Parsing:

__freading example.grammar input.txt output.json

This command uses the grammar defined in example.grammar to parse the data in input.txt and generates the output as JSON in output.json.

Complex Transformation:

__freading -f complex.grammar input.xml output.csv --verbose

This command uses the complex.grammar for parsing the XML data in input.xml. It generates a comma-separated value (CSV) file as output in output.csv and provides verbose logging during execution.

Common Issues

  • Invalid Grammar: Ensure the specified grammar file is valid and adheres to the correct syntax.
  • Missing Input File: Specify an existing input file as the third argument.
  • Output File Access: Make sure the output file can be created or overwritten in the specified location.


freading can be integrated into scripts or command chains for advanced data processing tasks, such as:

  • Automated Data Extraction: Parse structured data from various sources and extract specific information.
  • Data Transformation: Convert data from one format to another using custom rules defined in the grammar.
  • Data Validation: Check data integrity based on predefined rules and report any discrepancies.

Related Commands

  • sed: Perform text substitution and editing operations.
  • grep: Search for specific patterns in text.
  • awk: Process text data using programming logic.