grep: Difference between revisions
from HTYP, the free directory anyone can edit if they can prove to me that they're not a spambot
extracted manpage transcrip to a subpage; reference links |
→Notes: integrated most of these with the file-masks subpage |
||
| (5 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
<hide> | |||
[[page type::manual]] | |||
[[thing type::command]] | |||
[[platform::Linux]] | |||
</hide> | |||
==Pages== | ==Pages== | ||
* {{l/manpage}} - the current [[manpage]] | * {{l/manpage}} - the current [[manpage]] | ||
* [[/manpage]] - a nicely-formatted but old version of the grep manpage | * [[/manpage]] - a nicely-formatted but old version of the grep manpage | ||
==Examples== | |||
; grep ''text_to_find'' *.log:find ''[text_to_find]'' by checking all the logfiles in the current folder | |||
; grep -r ''text_to_find'' *:find ''[text_to_find]'' by checking all files in the current folder or under it | |||
Note that you can't do e.g. <code>grep -r ''[text_to_find]'' *.log</code> because that will only search in folders named <code>''[something]''.log</code>. [[/file masks|The reasons for this are complicated.]] | |||
==Questions== | ==Questions== | ||
* So, how do you grep for a string which contains spaces and quote characters? This is probably some standard feature of Linux Shell syntax which everyone knows, but I don't, and that's why this page needs examples. | * So, how do you grep for a string which contains spaces and quote characters? This is probably some standard feature of Linux Shell syntax which everyone knows, but I don't, and that's why this page needs examples. | ||
*: '''A''': Tentatively, you can surround a string with double-quotes and escape any quotes in the search-string with the backslash character. (Single quotes do not seem to work.) | |||
* Likewise, how do you search a group of files? Using "*.*" for FILE doesn't seem to work, and leaving the FILE argument blank tells grep to expect input from STDIN. | * Likewise, how do you search a group of files? Using "*.*" for FILE doesn't seem to work, and leaving the FILE argument blank tells grep to expect input from STDIN. | ||
*: '''A:''' apparently "*" by itself; see examples | *: '''A:''' apparently "*" by itself; see examples above | ||
==Notes== | |||
== | The backtick character ("`") seems to mean "insert the output of this command here" -- so if you're trying to search for a literal backtick, it needs to be escaped with "\" ("\`"). This comes up sometimes when searching for [[SQL]] phrases. | ||
==Links== | ==Links== | ||
* [http://www.gnu.org/software/grep/manual/ official documentation]: more current than the manpage | * [http://www.gnu.org/software/grep/manual/ official documentation]: more current than the manpage on this server | ||
* {{wikipedia}} | * {{wikipedia}} | ||
Latest revision as of 15:13, 21 June 2022
<hide> page type::manual thing type::command platform::Linux </hide>
Pages
Examples
- grep text_to_find *.log
- find [text_to_find] by checking all the logfiles in the current folder
- grep -r text_to_find *
- find [text_to_find] by checking all files in the current folder or under it
Note that you can't do e.g. grep -r [text_to_find] *.log because that will only search in folders named [something].log. The reasons for this are complicated.
Questions
- So, how do you grep for a string which contains spaces and quote characters? This is probably some standard feature of Linux Shell syntax which everyone knows, but I don't, and that's why this page needs examples.
- A: Tentatively, you can surround a string with double-quotes and escape any quotes in the search-string with the backslash character. (Single quotes do not seem to work.)
- Likewise, how do you search a group of files? Using "*.*" for FILE doesn't seem to work, and leaving the FILE argument blank tells grep to expect input from STDIN.
- A: apparently "*" by itself; see examples above
Notes
The backtick character ("`") seems to mean "insert the output of this command here" -- so if you're trying to search for a literal backtick, it needs to be escaped with "\" ("\`"). This comes up sometimes when searching for SQL phrases.
Links
- official documentation: more current than the manpage on this server
- Wikipedia
