Howdy!
I'm trying to automate editing of a configuration file (custom.conf for GDM). I need to find every line between a line that starts with "" and the next line that starts with "", I want to preserve that line, but then delete all the lines in that configuration section and then insert... (3 Replies)
Hi,
I have a situation where I want to replace some occurrences of ".jsp" into ".html" inside a text file.
For Example:
If a pattern found like <a href="http://www.mysite.com/mypage.jsp"> it should be retained.
But if a pattern found like <a href="../mypage.jsp"> it should be changed to... (4 Replies)
Hello,
file1:
not to be changed
not to be changed
<start>
old stuff
old stuff
old stuff
<end>
not to be changed
not to be changed
file2:
new text
new text
desired output: (3 Replies)
can anyone please help me in the below scenario:
File1:
Hello1
Hello1
i want to use sed to replace multiple occurances of Hello1 in file 1 to welcome.
Thanks a ton for the help (9 Replies)
Hello, guys!
"filename" has blocks with three lines each in this fashion:
93909286
#verified
has one bug
10909286
#unverified
pending
10909286
#unverified
pendingThe above example has duplicate blocks, and I have tried using sed to remove just one block... The... (2 Replies)
Hi,
I would like to use sed to replace NA to x ('s/NA/x/g'), but only in the 5th column of the space delimited text file, nowhere else. How do I go about doing that? Thanks! (1 Reply)
Hi,
I want to use sed to replace " /// " with "///" in a text file. However I am getting error messages when I use sed 's/ /// /////g' input.txt > output.txt. How do I go about doing this in sed?
Input:
219518_s_at 0.000189 ELL3 / SERINC4
Output:
219518_s_at 0.000189 ELL3/SERINC4 (5 Replies)
I have a sample text format as given below
<Text Text_ID="10155645315851111_10155645333076543" From="460350337461111" Created="2011-03-16T17:05:37+0000" use_count="123">This is the first text</Text>
<Text Text_ID="10155645315851111_10155645317023456" From="1626711840902323"... (3 Replies)
Good Day Every one
I have a problem finding and replacing text in some large files that will take a long time to manually edit.
Example text file looks like this
#Example Large Text File
unix
linux
dos
squid
bind
dance
bike
car
plane
What im trying to do is to edit all the... (4 Replies)
Hello Everyone,
I have many files like so:
file1.txt
file2.txt
file3.txt
Within each file I have many lines of random text separated by commas like so:
abcAAA,123,defAA,456777,ghiA,789
jklB,101,mnoBBB,11211,pqrB,13111
stuCC,415,vwxCCCC,161,yzaC,718
I am trying to use SED or AWK to... (4 Replies)
Discussion started by: D3U5X
4 Replies
LEARN ABOUT MOJAVE
perlrequick5.18
PERLREQUICK(1) Perl Programmers Reference Guide PERLREQUICK(1)NAME
perlrequick - Perl regular expressions quick start
DESCRIPTION
This page covers the very basics of understanding, creating and using regular expressions ('regexes') in Perl.
The Guide
Simple word matching
The simplest regex is simply a word, or more generally, a string of characters. A regex consisting of a word matches any string that
contains that word:
"Hello World" =~ /World/; # matches
In this statement, "World" is a regex and the "//" enclosing "/World/" tells Perl to search a string for a match. The operator "=~"
associates the string with the regex match and produces a true value if the regex matched, or false if the regex did not match. In our
case, "World" matches the second word in "Hello World", so the expression is true. This idea has several variations.
Expressions like this are useful in conditionals:
print "It matches
" if "Hello World" =~ /World/;
The sense of the match can be reversed by using "!~" operator:
print "It doesn't match
" if "Hello World" !~ /World/;
The literal string in the regex can be replaced by a variable:
$greeting = "World";
print "It matches
" if "Hello World" =~ /$greeting/;
If you're matching against $_, the "$_ =~" part can be omitted:
$_ = "Hello World";
print "It matches
" if /World/;
Finally, the "//" default delimiters for a match can be changed to arbitrary delimiters by putting an 'm' out front:
"Hello World" =~ m!World!; # matches, delimited by '!'
"Hello World" =~ m{World}; # matches, note the matching '{}'
"/usr/bin/perl" =~ m"/perl"; # matches after '/usr/bin',
# '/' becomes an ordinary char
Regexes must match a part of the string exactly in order for the statement to be true:
"Hello World" =~ /world/; # doesn't match, case sensitive
"Hello World" =~ /o W/; # matches, ' ' is an ordinary char
"Hello World" =~ /World /; # doesn't match, no ' ' at end
Perl will always match at the earliest possible point in the string:
"Hello World" =~ /o/; # matches 'o' in 'Hello'
"That hat is red" =~ /hat/; # matches 'hat' in 'That'
Not all characters can be used 'as is' in a match. Some characters, called metacharacters, are reserved for use in regex notation. The
metacharacters are
{}[]()^$.|*+?
A metacharacter can be matched by putting a backslash before it:
"2+2=4" =~ /2+2/; # doesn't match, + is a metacharacter
"2+2=4" =~ /2+2/; # matches, + is treated like an ordinary +
'C:WIN32' =~ /C:\WIN/; # matches
"/usr/bin/perl" =~ //usr/bin/perl/; # matches
In the last regex, the forward slash '/' is also backslashed, because it is used to delimit the regex.
Non-printable ASCII characters are represented by escape sequences. Common examples are " " for a tab, "
" for a newline, and "
" for a
carriage return. Arbitrary bytes are represented by octal escape sequences, e.g., "