Searching text files with GNU Grep utility

I enjoy sharing tips of something I’ve picked up with the hope it helps others.  GREP is a common utility in the Unix world (thatis what I hear anyway), it’s something I’ve never really dug into.  The day came I found a tip to pass along.  I needed to search non-structured text files looking for specific text. I couldn’t find a clean way using Log Parser or Findstr utilities, these are two common tools I use.  Updated – Here is the link I used to install on Windows http://gnuwin32.sourceforge.net/packages/grep.htm


What impressed me I could search for a set of text that contains commas, slashes and other normal separators as one string of text.   Here is an example of what I was looking for.  I tried the Windows Services for Unix utilities, but GNU Grep seemed more straight forward.


grep -i ‘example.com,max value, (Megabits/s)’ menu.h main.c


Usage: grep [OPTION]… PATTERN [FILE] …
Search for PATTERN in each FILE or standard input.
Example: grep -i ‘hello world’ menu.h main.c


Regexp selection and interpretation:
  -E, –extended-regexp     PATTERN is an extended regular expression
  -F, –fixed-strings       PATTERN is a set of newline-separated strings
  -G, –basic-regexp        PATTERN is a basic regular expression
  -P, –perl-regexp         PATTERN is a Perl regular expression
  -e, –regexp=PATTERN      use PATTERN as a regular expression
  -f, –file=FILE           obtain PATTERN from FILE
  -i, –ignore-case         ignore case distinctions
  -w, –word-regexp         force PATTERN to match only whole words
  -x, –line-regexp         force PATTERN to match only whole lines
  -z, –null-data           a data line ends in 0 byte, not newline


Miscellaneous:
  -s, –no-messages         suppress error messages
  -v, –invert-match        select non-matching lines
  -V, –version             print version information and exit
      –help                display this help and exit
      –mmap                use memory-mapped input if possible


Output control:
  -m, –max-count=NUM       stop after NUM matches
  -b, –byte-offset         print the byte offset with output lines
  -n, –line-number         print line number with output lines
      –line-buffered       flush output on every line
  -H, –with-filename       print the filename for each match
  -h, –no-filename         suppress the prefixing filename on output
      –label=LABEL         print LABEL as filename for standard input
  -o, –only-matching       show only the part of a line matching PATTERN
  -q, –quiet, –silent     suppress all normal output
      –binary-files=TYPE   assume that binary files are TYPE
                            TYPE is ‘binary’, ‘text’, or ‘without-match’
  -a, –text                equivalent to –binary-files=text
  -I                        equivalent to –binary-files=without-match
  -d, –directories=ACTION  how to handle directories
                            ACTION is ‘read’, ‘recurse’, or ‘skip’
  -D, –devices=ACTION      how to handle devices, FIFOs and sockets
                            ACTION is ‘read’ or ‘skip’
  -R, -r, –recursive       equivalent to –directories=recurse
      –include=PATTERN     files that match PATTERN will be examined
      –exclude=PATTERN     files that match PATTERN will be skipped.
      –exclude-from=FILE   files that match PATTERN in FILE will be skipped.
  -L, –files-without-match only print FILE names containing no match
  -l, –files-with-matches  only print FILE names containing matches
  -c, –count               only print a count of matching lines per FILE
  -Z, –null                print 0 byte after FILE name


Context control:
  -B, –before-context=NUM  print NUM lines of leading context
  -A, –after-context=NUM   print NUM lines of trailing context
  -C, –context=NUM         print NUM lines of output context
  -NUM                      same as –context=NUM
      –color[=WHEN],
      –colour[=WHEN]       use markers to distinguish the matching string
                            WHEN may be `always’, `never’ or `auto’.
  -U, –binary              do not strip CR characters at EOL (MSDOS)
  -u, –unix-byte-offsets   report offsets as if CRs were not there (MSDOS)


`egrep’ means `grep -E’.  `fgrep’ means `grep -F’.
With no FILE, or when FILE is -, read standard input.  If less than
two FILEs given, assume -h.  Exit status is 0 if match, 1 if no match,
and 2 if trouble.

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