====== grep ======
http://www.gnu.org/software/grep/
===== Command line usage =====
grep [options] PATTERN [FILE...]
grep [options] [-e PATTERN | -f FILE] [FILE...]
===== Examples =====
|printenv | grep lib|print a list of environment variables that contain "lib"|
|grep -e foo -R -n . |search from current directory and below, inside of files for "foo", and print a list of file paths, line numbers, and lines that match|
|grep -e foo -R -l . |search from current directory and below, inside of files for "foo", and only print a list of files that match|
|grep -i foo -R -l . |same as previous, but case insensitive "foo" (foo, Foo, FOO, etc...)|
===== Complex Examples =====
* find all todo's and fixme's, ignoring case, from this directory and deeper, ignoring any results with .svn or .loggrep -R -n -iE 'todo|fixme' . | grep -v -E '\.svn|\.log'
* search all files in this directory and lower, finding carriage returns (\r, ^M)
grep -U -R -P '\x0d' *
or list files only (this example uses octal carriage return)
grep -U -R -l -P '\015' *