Tagged Questions
2
votes
1answer
82 views
escaping a single dot with double backslash - awk
"effective awk programming" book has an example on Field-Splitting. here is the example:
If you want fields to be separated by a literal period
followed by any single character, use ‘FS = ...
2
votes
1answer
70 views
remove trailing zeros in awk not working. syntax error
regex = "\\.*0+$";
subst = "";
system("echo "id "| awk '{sub(\\.*0+$," subst"); print}'");
It is giving the following error:
awk: cmd. line:1: {sub(\.*0+$,); print}
awk: cmd. line:1: ^ ...
3
votes
5answers
125 views
changing pattern of a text file
A text file has contents something like
chair
table
pen
desk
Now i want it to be changed and stored in a variable say var as below
('chair','chair'),('table','table'),('pen','pen'),('desk','desk')
...
3
votes
3answers
86 views
Awk: check for length of field
In awk. I am working on Solaris 10, so it's probably an old(er) version of awk.
I came up with this rudimentary one-liner that works, at least for my particular input.
awk -F\; '$3 ~ /[ ...
1
vote
2answers
111 views
How can I match this text in awk, printing line numbers for matches?
I have a text file thousands (roughly 148,000 lines long) that consists of a lot of sequences like this:
b 29.
b 52.
c 84.
c 83.
c 94.
c 93.
c 61.
b 38.
c 81.
c 92.
c 28.
c 37.
c 27.
... and since ...
8
votes
6answers
256 views
Delete lines beginning with #
How do I delete lines beginning with a #, given that there can be whitespace on the left and right of the #?
# Master socket provides access to userdb information. It's typically
3
votes
0answers
127 views
How to use regrex with AWK for string replacement in this example? [closed]
Possible Duplicate:
How to use regrex with AWK for string replacement in this example?
Suppose there is some text from a file:
(bookmarks
("Chapter 1 Introduction 1" "#1"
("1.1 Problem ...
1
vote
3answers
623 views
How to use regrex with AWK for string replacement in this example?
Suppose there is some text from a file:
(bookmarks
("Chapter 1 Introduction 1" "#1"
("1.1 Problem Statement and Basic Definitions 23" "#2")
("Exercises 31" "#30")
("Notes and References 42" "#34"))
)
...
1
vote
2answers
153 views
pattern search and display the last occuring pattern?
I have a log file containing startup and shutdown times for everday.
I want to see the last pattern pattern for startup and shutdown(which is located at the end of the file being updated everyday).
...
5
votes
2answers
195 views
How to use regex as field separator in awk?
I'm trying to use regex as a field seperator in awk. From my reading this seems possible but I can't get the syntax right.
rpm -qa | awk '{ 'FS == [0-9]' ; print $1 }'
awk: cmd. line:1: { FS
awk: ...
3
votes
3answers
102 views
What does . match?
In working with regular expressions, I have been told that a dot character . will match everything.
Except for newlines \n.
Are there any other exceptions? What about the NUL character \0, or the ...
3
votes
1answer
163 views
Why are capital letters included in a range of lower-case letters in an awk regex?
$ echo ABC | awk '$0 ~ /^[a-b]/'
ABC
$ echo ABC | awk '$0 ~ /^[a-a]/'
$ echo ABC | awk '$0 ~ /^a/'
$
You see. /[a-b]/ captures A, but /[a-a]/ or /a/ doesn't. Why?
4
votes
6answers
569 views
How can you combine all lines that end with a backslash character?
Using a common command line tool like sed or awk, is it possible to join all lines that end with a given character, like a backslash?
For example, given the file:
foo bar \
bash \
baz
dude \
happy
...
2
votes
1answer
336 views
Using grep/sed/awk to classify log file entries
I need to process a very large log file with many lines in different formats.
My goal is to extract unique line entries who have the same starting pattern, e.g. '^2011-02-21.*MyKeyword.*Error', ...
9
votes
8answers
667 views
There must be a better way to replace single newlines only?
I am in the habit of writing one line per sentence because I typically compile things to LaTex, or am writing in some other format where line breaks get ignored. I use a blank line to indicate the ...
