, Linux . , find. grep, .
grep-?
Grep Linux, . . grep, .
ls. .

, ls grep (|), grep- .
$ ls | grep Documents

grep , / .

, , grep . Grep , .
$ ls | grep 'My Documents'

, grep , .
$ grep 'Class 1' Students.txt

Students.txt grep .
grep , . e. , "-" . , , .
$ grep -e 'Class 1' -e Todd Students.txt

grep, egrep fgrep, pgrep, zgrep
Linux- grep. grep , egrep fgrep, pgrep, zgrep, .

man grep ( grep), . , egrep , grep E (, Linux grep e grep E ). . , . , , "p".
$ egrep p\{2} fruits.txt $ grep -E p\{2} fruits.txt

Fgrep grep F, . , , grep .

pgrep , (PID). PID sshd. ps e | grep sshd.
$ pgrep sshd

zgrep , , .
$ zgrep apple fruits.txt.gz

Zgrep tar , , . , gzip- tar .

find grep
, Linux , find grep , , "" -.
grep- find, . - ( *), find. .
$ find /path/to/search -name name-of-file

, grep r. , , . .
$ grep -r pattern /directory/to/search

, , . . .
$ grep " " sample.txt

, . , Linux TAB . ctrl+v, TAB, . $ grep " " sample.txt

, .
grep, . .
[ ] .
$ grep "Class [123]" Students.txt

[-] . , .
$ grep "Class [1-3]" Students.txt

, , .
^ , . , "".
$ grep "^A" Students.txt

[^] . .
$ grep "Class [^1-2]" Students.txt

$ . , .
$ grep "1$" Students.txt

. . , .
$ grep "A.a" Students.txt

.
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{n} |
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{3} |
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{m,n} |
m n |
{2,4} |
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{0,1} |
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gz
, zgrep. , , grep .
$ zcat file.gz | grep word-to-search

e-mail - . . grep .
$ grep -o '[[:alnum:]+\.\_\-]*@[[:alnum:]+\.\_\-]*' emails.txt
o , e-mail , , e-mail.

, Linux . . egrep . , .
IP
IP , , . , , IP . IP .
$ grep -E -o "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)" /var/log/auth.log
IP, SSH.

(OR) grep. .
$ grep -E 'string1|string2' filename $ egrep 'string1|string2' filename

, grep , , . i .
$ grep -i string filename

, .
, , , ? Grep i . .
$ grep [Ss]tring filename

, apple. .
$ grep "\<apple\>" fruits.txt

w. , , .
v.
$ grep -v string-to-exclude filename

grep, , sed. "string1", "string2" .
$ grep -rl 'string1' ./ | xargs sed -i 's/string1/string2/g'
, , grep n.
$ grep -n string filename

, . grep c .
$ grep -c 1 string filename

grep - , sort (|). sort .

. .