Diff for "BashFAQ/008"

Differences between revisions 2 and 10 (spanning 8 versions)

How can I recursively search all files for a string?

90% of the time, all you need is one of these:

# Recurse and print matching lines (GNU grep):
grep -r "$search" .

# Recurse and print only the filenames (GNU grep):
grep -r -l "$search" .

You can use find if your grep lacks a -r option:

find . -type f -exec grep -l "$search" {} \;

The {} characters will be replaced with the current file name.

This command is slower than it needs to be, because find will call grep with only one file name, resulting in many grep invocations (one per file). Since grep accepts multiple file names on the command line, find can be instructed to call it with several file names at once:

find . -type f -exec grep -l "$search" {} +

The trailing '+' character instructs find to call grep with as many file names as possible, saving processes and resulting in faster execution. This example works for POSIX find, e.g. with Solaris, as well as very recent GNU find.

Traditional Unix has a helper program called xargs for the same purpose:

find . -type f | xargs grep -l "$search"

However, if your filenames contain spaces or other metacharacters, you'll need to use the BSD/GNU -print0 option:

find . -type f -print0 | xargs -0 grep -l "$search"

The -print0 / -0 options ensure that any file name can be processed, even one containing blanks, TAB characters, or newlines.

CategoryShell

-  ⇤ ← Revision 2 as of 2007-05-07 19:01:09 → 
  Size: 1431
  Editor: GreyCat
  Comment: clean up in aisle 8
+   ← Revision 10 as of 2010-06-28 18:55:10 → ⇥
  Size: 1610
  Editor: 88-104-22-8
  Comment: Typo
-Deletions are marked like this.
+Additions are marked like this.
 Line 1:
-[[Anchor(faq8)]]
+<<Anchor(faq8)>>
-Line 3:
+Line 4:
 Line 13:
+You can use [[UsingFind|find]] if your {{{grep}}} lacks a {{{-r}}} option:
-Line 14:
+Line 15:
-You can use [:UsingFind:find] if your {{{grep}}} lacks a {{{-r}}} option:
 Line 18:
-Line 22:
+Line 21:
 Line 25:
-Line 28:
+Line 27:
-GNU (and recent BSD) {{{find}}} commands use a helper program called {{{xargs}}} for the same purpose:
+Traditional Unix has a helper program called {{{xargs}}} for the same purpose:

{{{
find . -type f | xargs grep -l "$search"
}}}
However, if your filenames contain spaces or other metacharacters, you'll need to use the BSD/GNU {{{-print0}}} option:
-Line 32:
+Line 37:
+The {{{-print0}}} / {{{-0}}} options ensure that any file name can be processed, even one containing [[BashFAQ/020|blanks, TAB characters, or newlines]].
-Line 33:
+Line 39:
-The {{{-print0}}} / {{{-0}}} options ensure that any file name can be processed, even ones containing [#faq20 blanks, TAB characters, or newlines].
+----
CategoryShell