10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
echo 20110101 | awk '{ print match($0,/^((17||18||19||20)|)-*(|0|1)-*(|0||3)$/))
I am getting a match for the above, where as it shouldn't, as there is no hyphen in the echoed date.
Another question is what is the difference between || and | in the above statement (4 Replies)
Discussion started by: tostay2003
4 Replies
2. Shell Programming and Scripting
Using a regular expression, I would like multiple lines to be matched.
By default, a period (.) matches any character except newline. However, (?s) and /s modifiers are supposed to force . to accept a newline and to match any character including a newline.
However, the following two perl... (4 Replies)
Discussion started by: LessNux
4 Replies
3. Shell Programming and Scripting
I cannot seem to get this to work correct:
my ($k, $v) = split(/F/, $fc{$DIR}{symbolic}, 2);
Below is the input (the $fc{$DIR}{symbolic} variable):
QMH2562 FW:v5.06.03 DVR:v8.03.07.15.05.09-kbut i also need it to break on FV:
Emulex NC553i FV4.2.401.6 DV8.3.5.86.2pthe code above... (2 Replies)
Discussion started by: rusted_planet
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4. Homework & Coursework Questions
Hi Everybody!
I need some help with a regular expression in Perl that will match files named messages, but also files named message.1, message.2 and so on. So really I need one that will find messages and messages that might be followed by a period and a digit without matching other files like... (2 Replies)
Discussion started by: Hax0rc1ph3r
2 Replies
5. Shell Programming and Scripting
hi everyone
suppose we have two scenario
echo ABCD | grep \{4\}
DATE
echo SYSDATE | grep \{4\}
SYSDATE
i want to match the string of four length only please help (5 Replies)
Discussion started by: aishsimplesweet
5 Replies
6. Shell Programming and Scripting
I am trying to match a similar line using grep with regular expression
the line is
/remote/mac/pbbbb/abc/def/hij/hop/include/abc/tif/element/test/testfiles/Office.cpp:57: const OfficeType& getType().get() const;
I just need to extract the bold characters using grep with regular expression.... (5 Replies)
Discussion started by: prasbala
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7. Shell Programming and Scripting
Hi all,
I am looking for a regex syntax to match repeated appearance. Likes,
']+]+' matches for string '65A SOME MORE AND 78B'
Now, this gets messy if I need to extract all such repeated appearance. I don't want to write ] four or five times for matching repeated appearance.
Thanks in... (2 Replies)
Discussion started by: guruparan18
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8. Shell Programming and Scripting
Hello All
I have file which contain sample data like below -
test.txt
----------------------------------------------
jambesh aaa india
trxxx
sdasd
mentor
asss
light
train
bbblah
---------------------------------------------
I want to write a regX which would print only those... (4 Replies)
Discussion started by: jambesh
4 Replies
9. Shell Programming and Scripting
Hi all,
any idea how to match the following:
char*<no or any string or space> buf and
char *<no or any string or space> buf
i need to capture the buf characters too.
currently i need two checks to cover this:
#search char* <any string> buf or char *<any string> buf
@noarray =... (2 Replies)
Discussion started by: ChaMeN
2 Replies
10. UNIX for Dummies Questions & Answers
Hi,
I'm struggling with a regex that would match a 'b' that follows an 'a' and is at the end of a string of non-white characters. For example:
Line 1: aba abab b abb aab bab baa
I can find the right strings but I'm lacking knowledge of how to "discard" the bits that precede bs.... (2 Replies)
Discussion started by: machinogodzilla
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GREP(1) General Commands Manual GREP(1)
NAME
grep, egrep, fgrep - search a file for a pattern
SYNOPSIS
grep [ option ] ... expression [ file ] ...
egrep [ option ] ... [ expression ] [ file ] ...
fgrep [ option ] ... [ strings ] [ file ]
DESCRIPTION
Commands of the grep family search the input files (standard input default) for lines matching a pattern. Normally, each line found is
copied to the standard output; unless the -h flag is used, the file name is shown if there is more than one input file.
Grep patterns are limited regular expressions in the style of ed(1); it uses a compact nondeterministic algorithm. Egrep patterns are full
regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space. Fgrep patterns are fixed strings; it
is fast and compact.
The following options are recognized.
-v All lines but those matching are printed.
-c Only a count of matching lines is printed.
-l The names of files with matching lines are listed (once) separated by newlines.
-n Each line is preceded by its line number in the file.
-b Each line is preceded by the block number on which it was found. This is sometimes useful in locating disk block numbers by con-
text.
-s No output is produced, only status.
-h Do not print filename headers with output lines.
-y Lower case letters in the pattern will also match upper case letters in the input (grep only).
-e expression
Same as a simple expression argument, but useful when the expression begins with a -.
-f file
The regular expression (egrep) or string list (fgrep) is taken from the file.
-x (Exact) only lines matched in their entirety are printed (fgrep only).
Care should be taken when using the characters $ * [ ^ | ? ' " ( ) and in the expression as they are also meaningful to the Shell. It is
safest to enclose the entire expression argument in single quotes ' '.
Fgrep searches for lines that contain one of the (newline-separated) strings.
Egrep accepts extended regular expressions. In the following description `character' excludes newline:
A followed by a single character matches that character.
The character ^ ($) matches the beginning (end) of a line.
A . matches any character.
A single character not otherwise endowed with special meaning matches that character.
A string enclosed in brackets [] matches any single character from the string. Ranges of ASCII character codes may be abbreviated
as in `a-z0-9'. A ] may occur only as the first character of the string. A literal - must be placed where it can't be mistaken as
a range indicator.
A regular expression followed by * (+, ?) matches a sequence of 0 or more (1 or more, 0 or 1) matches of the regular expression.
Two regular expressions concatenated match a match of the first followed by a match of the second.
Two regular expressions separated by | or newline match either a match for the first or a match for the second.
A regular expression enclosed in parentheses matches a match for the regular expression.
The order of precedence of operators at the same parenthesis level is [] then *+? then concatenation then | and newline.
SEE ALSO
ed(1), sed(1), sh(1)
DIAGNOSTICS
Exit status is 0 if any matches are found, 1 if none, 2 for syntax errors or inaccessible files.
BUGS
Ideally there should be only one grep, but we don't know a single algorithm that spans a wide enough range of space-time tradeoffs.
Lines are limited to 256 characters; longer lines are truncated.
GREP(1)