Here's the usage:
$ ./bgrep -h below cmd output started 2018 Tue Apr 24 06:08:53 PM PDT usage: bgrep [-e] [-b] [-A after_bytes] [-B before_bytes] [-o] pattern filelist -h output this help message -e echo pattern to stderr - for troubleshooting shell quoting issues -i ignore case -f flush frequently -b buffer_len defines the buffer length -o overlap_size defines the amount of overlap between two buffers -l list filenames along with the offsets -A num_bytes number of bytes to display after the match. Must include the match itself -B num_bytes number of bytes to display before the match pattern is an emacs-style regular expression filelist is a list of filenames
See also bcgrep for a tool that can grep without fouling your buffer cache.
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