escape-egrep

#!/usr/bin/python -tt
# vim: fileencoding=utf8
import sys
#{{{ License header: MIT
# Copyright (c) 2017 Till Maas <opensource@till.name>
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# Escape all egrep special characters found in stdin and write to stdout
# Useful for writing logcheck rules

if __name__ == "__main__":
    ifile = sys.stdin
    ofile = sys.stdout
    for line in ifile.xreadlines():
        for char in line:
            # escape egrep special char
            if char in r'.?*+[](){}^$\|':
                ofile.write('\\')
            ofile.write(char)