If you want just regex not commands, you are probably out of luck. The searches are too unrelated for one regex. What context do you want to use it in, if not a command?
For example in any programming language that supports pcre: C, perl, python, Ruby... of course every programming language has other ways to check this, for example in python:
I just want to know if it's possible to do that in a single regular expression, just out of curiousity and simply to get a better understanding of regexps.
I tried to do it like this:
But of course that doesn't work because [^\1] matches *all* the characters except the character that matched in the first parenthesis set... I think this should be done with some kind of backtracking.
And BTW I'm sure that it can be done with regexps! I mean, if you can test if a number is a primer number with regular expressions, I refuse to believe this simple thing can't be done
or I don't know how to make it work ...
Hello
im trying to build regexp that will match me single string or function call inside of brackets
for example I have :
<% myFunction("blah",foo) %>
or
<% myVar %>
and not match :
<% if(myFunction("blah",foo)==1) %>
or
<% while(myvar < 3){... (2 Replies)
Hi everybody
for file in *
#Bash performs filename expansion
#+ on expressions that globbing recognizes.
do
output="`grep -n "$1" "$file"`"
echo "$file: `expr "$output" : '\(^.*$\)'`"
done
In the above bash script segment, I try to print just the first line of string named... (3 Replies)
Hi. Here's a tricky one (at least to me):
I have a file named theFile.txt (UTF-8) that contains the following:
a
b
cWhen I execute
perl -pe 's|a.*c|d|sg' theFile.txtin bash 3.2 on MAC OS X 10.6, I get no match, i.e. the result is
a
b
cagain. Any clues why? (2 Replies)
Hi,
I searched in the forums, but I didn't find a good solution. My problem is:
I have a string like "TEST.ABC201005.MONTHLY.D101010203".
I just want to have the string until the D100430, so that the string should look like: "TEST.ABC201005.MONTHLY.D"
The last characters after the D can be... (8 Replies)
Hello everyone,
I'm new in tcl scripting.
I'm currently studying a tcl script and came across this line:
regexp {(\d+)(\S?)} $opts match opt swi
According to my understanding, this line means to search in the opts variable for one or more digit, followed by a non-whitespace character... (2 Replies)
I'm probably just not thinking of the correct term to search for :-) But I want to match a pattern that might be 'ABC' or '1ABC' there might be three characters, or there might be four, but if there are four, the first has to be 1 (1 Reply)
Hi All,
I have a file fo around 15k bytes which i need to insert a string " + "at every 250 bytes.
I found some ideas here using perl to split into lines and tried to addapt it but the results where not satisfactory
for instance i tried to change
#!/usr/bin/perl
$teststring =... (9 Replies)
Greetings Experts,
I am in AIX; I have a file generated through awk after processing the input files. Now I need to replace or remove the new-line characters on all lines that doesn't have a ; which is the last character on the line. I tried to use sed 's/\n/ /g' After checking through the... (6 Replies)
For a given string that may contain any ASCII chars, i.e. that matches .*,
find and print only the chars that are in a given subset.
The string could also have numbers, uppercase, special chars such as ~!@#$%^&*(){}\", whatever a user could type in
without going esoteric
For simplicity take... (1 Reply)
Hi All,
I need to print the characters in the previous line just before the regular expression match
Please have a look at the input file as attached
I need to match the regular expression ^ with the character of the previous like and also the pin numbers
and the output file should be like... (6 Replies)
Discussion started by: kshitij
6 Replies
LEARN ABOUT BSD
grep
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. Grep patterns are limited regular expressions in the style of ex(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.
-x (Exact) only lines matched in their entirety are printed (fgrep only).
-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 relative 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.
-i The case of letters is ignored in making comparisons -- that is, upper and lower case are considered identical. This applies to
grep and fgrep only.
-s Silent mode. Nothing is printed (except error messages). This is useful for checking the error status.
-w The expression is searched for as a word (as if surrounded by `<' and `>', see ex(1).) (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.
In all cases the file name is shown if there is more than one input file. 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 other than newline matches that character.
The character ^ matches the beginning of a line.
The character $ matches the end of a line.
A . (period) 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 an * (asterisk) matches a sequence of 0 or more matches of the regular expression. A regular
expression followed by a + (plus) matches a sequence of 1 or more matches of the regular expression. A regular expression followed
by a ? (question mark) matches a sequence of 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.
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.
SEE ALSO ex(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
Lines are limited to 256 characters; longer lines are truncated.
4th Berkeley Distribution April 29, 1985 GREP(1)