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Asked: 2009-12-04 06:09:26 +0800 CST

How do I make (non-gnu-)grep ignore binary files?

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Hey, I am on a HP-UX server here. When recursively grepping a directory tree, I have problems when the tree also contains binary files: grep treats them as text files and displays very long lines containing a lot of non-printable characters. This not only makes the output hard to scan, but also often makes my terminal unusable (and writes funny strings to its title).

GNU-grep has an option --binary-file= which would help (and it does not print the matching line anyway for binary files), but I do not have GNU-tools availabe.

Is there a way to simulate the behavior of GNU-grep or to ignore files that look like they are binary?

Btw. if there is an easy way to do this in perl, that would be fine, too.

unix

2 Answers

  1. Building on the previous answer, you can use the "file" command to identify text files, and then limit your grep to only those files. For example:

      find dir -type f -print |
    xargs file |
    grep text |
    cut -f1 -d: |
    xargs grep "expression"

    That's:

    • Find all files in directory "dir"
    • Pass these as arguments to "file"
    • Look for output from "file" containing the word "text"
    • Chop out the first colon-delimited field and use it as a filename
    • Search these files using grep.

    This will fail in the case of filenames containing whitespace or colons, but will otherwise do what you want.

    • 3

  2. There might be a better way, but maybe pass all the files to a shell loop, and do something like the following with the file command:

    if file "$i" | grep text; then
  ...
fi

    ...?

    • 1