Some more grep stuff April 11, 2010
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The grep command is a command used in Unix like systems to search.  When paired with the cat command, you can search a text file for any text string.  However, you might have to do a few things to find exactly what you are looking for.

Mainly, grep doesn’t like it if you use certain characters, it assumes that the capitalization is exactly the same, and it only shows the matching lines.  After quickly displaying the manual page for grep by running the following command, I learned a few neat things.

  • man grep

Below are commands that you type after grep and before your search string.  The description for each command is below the command.

  • -i
    • Match the search string, ignoring capitalization.  This tends to run somewhat slower than a normal search.
  • -c
    • Only display a number which is the number of lines which match your search query.  Not too useful.
  • –color
    • With two –  marks before the word color, NOT ONE, this command highlights your search term in each line.  Only works in the last grep command if you are using | symbols to run a search on a search.  Of course, your terminal must support colors.
  • -A #
  • -B #
  • -C #
    • Display # lines before (A), after (B), or around (C) the search query where # is a number.  All capital letters by the way.
  • -F
    • Capital F, this commands grep to search for you search string as you literally typed it.  Therefore, it will search for odd characters such as [ and ] in your search query.

It should be noted that you cannot use characters such as | in your queries because the Bash shell (which is what Cygwin uses) has a special meaning behind that character.  So, to search for that, put \ before each of them.  So, for a clan tag, you can type something like…

  • grep \|tag\|

One last thing too…  you don’t have to do the following…

  • cat file.txt | grep something | grep else

This command is the same, so you can just do away with the cat command.

  • grep something file.txt | grep else

Therefore, using these commands, I can search around as I prefer.  I recommend the -i and -C # and -F commands particularly.