What are alternative tools for searching files in full content?

Question

I realized that most of the text related tools I use, grep/egrep/awk/sed are line-oriented.
I guess that is a simplified approach to search in files but I was wondering if there is another set of tools operating on file level that I am not aware.

So are there other tools that search over the full contents of a file without using the line mode?

Answer 1

grep

If you're only interested in the names of the files that contain a search string 1 time you can use grep with its -l switch to do this.

Example

Say I have 2 files full of numbers.

$ seq 100 > sample1.txt
$ seq 100 > sample2.txt

Now if I search that file for occurrences of the string "10".

$ grep -l 10 sample*.txt 
sample1.txt
sample2.txt

It will only return the files that contain a match 1 time, even if there are multiple lines that match. As proof, if I take the -l switch out:

$ grep 10 sample*.txt 
sample1.txt:10
sample1.txt:100
sample2.txt:10
sample2.txt:100

pcregrep

If you want to search for patterns across multiple lines you can use pcregrep along with its -M switch, for multi-line.

$ pcregrep -M "11[\n,]*.*12" sample*
sample1.txt:11
12
sample2.txt:11
12

Answer 2

Perl gives you a "file slurp" mode:

echo "foo
bar
baz" |
perl -0777 -ne 'print "found it" if /foo\s+bar/'

The -0777 option is the key. The whole file gets read into memory, where you can operate on it.

Answer 3

For code, there's ack, it's awesome and can be language-specific or language-agnostic.

Answer 4

GNU coreutils documentation is nicely organized around files, lines, fields, and character oriented operations and tools that work on them. Check it out here.