bash - --line-regexp option with null data -

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consider command:

printf 'alpha\nbravo\ncharlie\n' | grep --line-regexp --quiet bravo

grep sees 3 lines separated newline, , matches bravo line. consider command:

printf 'alpha\0bravo\0charlie\0' | grep --line-regexp --quiet bravo

my thinking tells me because have not used --null-data, grep should see 1 or 0 lines separated newline, , fail match bravo followed newline. not, succeeds first command, why this?

this behavior was introduced grep 2.21:

when searching binary data, grep may treat non-text bytes line terminators. can boost performance significantly.

so happens binary data, non-text bytes (including newlines) treated line terminators. if want change behavior, can:

  • use --text. ensure newlines line terminators

  • use --null-data. ensure null bytes line terminators


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