argz_replace - Linux


The argz_replace utility is a versatile tool for modifying and restructuring argument lists. It provides a powerful way to manipulate arguments passed to scripts or programs.


argz_replace [options] <file> <start> <len> <replacement>


  • -a, –append: Append the replacement after the specified range.
  • -b, –before: Insert the replacement before the specified range.
  • -c, –count: Print the number of modified arguments instead of applying the change.
  • -f, –force: Overwrite existing arguments, even if they would be truncated.
  • -n, –null: Treat the argument list as null-terminated instead of whitespace-separated.
  • -o, –offset: Start counting the arguments from the specified offset.
  • -R, –retry: Retry the operation if the specified range is invalid.


Replace the third argument with "newarg":

argz_replace myfile 2 1 newarg

Insert "newarg" before the second argument:

argz_replace myfile 1 0 --before newarg

Print the count of modified arguments:

argz_replace myfile 2 1 newarg --count

Append "newarg" to the end of the argument list:

argz_replace myfile 0 0 --append newarg

Common Issues

  • Invalid Range: If the specified range is not valid (e.g., negative start or length), argz_replace will exit with an error code. Use the --retry option to handle invalid ranges.
  • Truncation: If the replacement is longer than the replaced range, existing arguments may be truncated. Use the --force option to overwrite arguments.


argz_replace can be integrated with other Linux commands or tools using shell pipelines or scripts. For example, to filter out arguments containing a specific string:

argz_replace myfile 0 0 | grep -v some_string

Related Commands

  • argz: A utility for working with argument lists.
  • fmtargz: A utility for formatting argument lists.
  • argz-parse: A utility for parsing argument lists.