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⇤ ← Revision 1 as of 2007-05-02 22:52:21
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Size: 1431
Comment: clean up in aisle 8
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| On most recent systems (GNU/Linux/BSD), you would use {{{grep -r pattern .}}} to search all files from the current directory (.) downward. | |
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| You can use {{{find}}} if your {{{grep}}} lacks -r: | 90% of the time, all you need is one of these: |
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| find . -type f -exec grep -l "$search" '{}' \; | # Recurse and print matching lines (GNU grep): grep -r "$search" . # Recurse and print only the filenames (GNU grep): grep -r -l "$search" . }}} You can use [:UsingFind:find] if your {{{grep}}} lacks a {{{-r}}} option: {{{ find . -type f -exec grep -l "$search" {} \; |
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| 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 instrumented to call it with several file names at once: | 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: |
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| find . -type f -exec grep -l "$search" '{}' \+ | find . -type f -exec grep -l "$search" {} + |
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| 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. | 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}}}. |
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| GNU find uses a helper program called {{{xargs}}} for the same purpose: | GNU (and recent BSD) {{{find}}} commands use a helper program called {{{xargs}}} for the same purpose: |
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| find . -type f -print0 | xargs -0 grep -l "$search" | find . -type f -print0 | xargs -0 grep -l "$search" |
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| The {{{-print0}}} / {{{-0}}} options ensure that any file name can be processed, even ones containing blanks, TAB characters, or new-lines. 90% of the time, all you need is: Have grep recurse and print the lines (GNU grep): {{{ grep -r "$search" . }}} Have grep recurse and print only the names (GNU grep): {{{ grep -r -l "$search" . }}} The {{{find}}} command can be used to run arbitrary commands on every file in a directory (including sub-directories). Replace {{{grep}}} with the command of your choice. The curly braces {} will be replaced with the current file name in the case above. (Note that they must be escaped in some shells, but not in ["BASH"].) |
The {{{-print0}}} / {{{-0}}} options ensure that any file name can be processed, even ones containing [#faq20 blanks, TAB characters, or newlines]. |
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 [:UsingFind: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.
GNU (and recent BSD) find commands use a helper program called xargs for the same purpose:
find . -type f -print0 | xargs -0 grep -l "$search"
The -print0 / -0 options ensure that any file name can be processed, even ones containing [#faq20 blanks, TAB characters, or newlines].