Hi ckwan,
Here is a version of the script with comments added. Let me know if something is still not clear.
For any Linux or UNIX system utility, you should be able to find out how it works by issuing the command:
If that doesn't work for you, try looking at the "Man Pages" section of this forum. The POSIX section gives you the (hopefully) portable subset of options for a utility that should work on most systems. For awk, that would be the POSIX awk utility description.
I avoided the simpler solution (suggested by Scrutinizer and Jotne) using RS= because although setting the input record separator to an empty string works on some implementations of awk; it is not portable. The standards only specify the behavior of an awk program if RS is defined to be a single character other than the NULL character.
Hi all
This is my output of the some SQL Query
TABLESPACE_NAME FILE_NAME TOTALSPACE FREESPACE USEDSPACE Free
------------------------- ------------------------------------------------------- ---------- --------- ---------... (2 Replies)
Hi folks,
I have a text file that I need to parse, and I cant figure it out. The source is a report breaking down softwares from various companies with some basic info about them (see source snippet below). Ultimately what I want is an excel sheet with only Adobe and Microsoft software name and... (5 Replies)
Hi,
I need to remove some lines from an XML file is the value within a tag is empty.
Imagine this scenario,
<acd><acdID>2</acdID><logon></logon></acd>
<acd><acdID></acdID><logon></logon></acd>
<acd><acdID></acdID><logon></logon></acd>
<acd><acdID></acdID><logon></logon></acd>
I... (3 Replies)
hi
my problem is little complicated one. i have 2 files which appear like this
file 1
abbsss:aa:22:34:as akl abc 1234
mkilll:as:ss:23:qs asc abc 0987
mlopii:cd:wq:24:as asd abc 7866
file2
lkoaa:as:24:32:sa alk abc 3245
lkmo:as:34:43:qs qsa abc 0987
kloia:ds:45:56:sa acq abc 7805
i... (5 Replies)
hi
i have an input file that contains some thing like this
aaa acc aa abc1 1232 aaa abc2....
poo awq aa abc1 aaa aaa abc2
bbb bcc bb abc1 3214 bbb abc3....
bab bbc bz abc1 3214 bbb abc3....
vvv ssa as abc1 o09 aaa abc4....
azx aaq aa abc1 900 aqq abc19....
aaa aa aaaa abc1 899 aa... (8 Replies)
hi
i have a set of similar files. i want to delete lines until certain pattern appears in those files. for a single file the following command can be used but i want to do it for all the files at a time since the number is in thousands.
awk '/PATTERN/{i++}i' file (6 Replies)
Hi Friends,
I have an input file like this
chr1 100 200
chr1 200 300
chr1 300 400
chr1 400 500
chr1 500 600
chr1 600 700
chr1 700 800
chr1 800 900
chr1 900 920
chr1 940 960
I would like to get the first line's second column and the fifth line's 3rd column as one single line. This... (13 Replies)
I want to keep last 2 days data from a file and want to delete others data from the file. Please help me.
Sample Input
# cat messages-2
Apr 15 11:25:03 test1 kernel: imklog 4.6.2, log source = /proc/kmsg started.
Apr 15 11:25:03 test1 rsyslogd: (re)start
Apr 16 19:42:03 test1 kernel:... (2 Replies)
Hi,
I have a file like below.
1,2,3,4,5,6,7,8,9I would like to print or copied to a file based of line count in perl
If I gave a condition 1 to 3 then it should iterate over above file and print 1 to 3 and then again 1 to 3 etc.
output should be
1,2,3
4,5,6
7,8,9 (10 Replies)
The awk below uses the tab-delimeted fileand reformats each line based on one of three conditions (rules). The 3 rules are for deletion (lines in blue), snv (line in red), and insertion (lines in green). I have included all possible combinations of lines from my actual data, which is very large.... (0 Replies)
Discussion started by: cmccabe
0 Replies
LEARN ABOUT PLAN9
grep
GREP(1) General Commands Manual GREP(1)NAME
grep - search a file for a pattern
SYNOPSIS
grep [ option ... ] pattern [ file ... ]
DESCRIPTION
Grep searches the input files (standard input default) for lines (with newlines excluded) that match the pattern, a regular expression as
defined in regexp(6). Normally, each line matching the pattern is `selected', and each selected line is copied to the standard output.
The options are
-c Print only a count of matching lines.
-h Do not print file name tags (headers) with output lines.
-i Ignore alphabetic case distinctions. The implementation folds into lower case all letters in the pattern and input before interpre-
tation. Matched lines are printed in their original form.
-l (ell) Print the names of files with selected lines; don't print the lines.
-L Print the names of files with no selected lines; the converse of -l.
-n Mark each printed line with its line number counted in its file.
-s Produce no output, but return status.
-v Reverse: print lines that do not match the pattern.
Output lines are tagged by file name when there is more than one input file. (To force this tagging, include /dev/null as a file name
argument.)
Care should be taken when using the shell metacharacters $*[^|()= and newline in pattern; it is safest to enclose the entire expression in
single quotes '...'.
SOURCE
/sys/src/cmd/grep.c
SEE ALSO ed(1), awk(1), sed(1), sam(1), regexp(6)DIAGNOSTICS
Exit status is null if any lines are selected, or non-null when no lines are selected or an error occurs.
GREP(1)