The grep -v "^$" is NOT just a sanity thing. It is a waste of system resources that only serves to make your script run slower. Any line that is matched by the first grep in your pipeline can't possibly be an empty line that will be discarded by the second grep in your pipeline. The cat in your pipeline is an unnecessary use of cat. It, again, only serves to make your script run slower.
The following script produces the same output as your script. But, of course, it depends on your sample input being a realistic sample of the actual contents of /tmp/x.txt. If it isn't, all bets are off.
This User Gave Thanks to Don Cragun For This Post:
All,
I have a task to search through several hundred files and extract duplicate detail records and keep them grouped with their header record. If no duplicate detail record exists, don't pull the header. For example, an input file could look like this:
input.txt
HA
D1
D2
D2
D3
D4
D4... (17 Replies)
I have a flat file and need to count no of records in the file less the header and the trailer record.
I would appreciate any and all asistance
Thanks
Hadi Lalani (2 Replies)
I am using HP UX and think this may be done with awk but bot sure.
I have a file with a several header records and undeneath many detail records I need to put in the header record the number of detail records above this header record and number of detail records below this header record
Header... (5 Replies)
Hello,
after 9 months of archiving 1000 files,
now, i need to change the order of fields in the header record.
some very large, space padded files.
HEADERCAS05212008D0210DOMEST01(spacepadded to record length 210)
must now be
05212008HEADERCASD0210DOMEST01(spacepadded to record length 210)
... (1 Reply)
Guys....
Got a scenario in which I need to skip parsing the header record while I do an awk.
Does awk has the flexibility to accomplish this?.
If so, how do we do this?.
Thanks !!!
-Anduzzi :) (2 Replies)
A header record is to be inserted in the begining of a flat file without using extra file or new file. It should be inserted into same file. Advace thanks for all help... (7 Replies)
I did some searches, but couldn't really find what I'm looking for. I have a file formatted as below:
BOF ABC CO - XYZ COMM DATA OF 07/05/2011
EBA00000001 sdfa rtyus uyml
EBB00000001 54682 984w3
EBA00000002 mkiyuasdf 98234
I want to pull the date from the header record and add it... (4 Replies)
Hi All,
I have got a requirement.
I have a source file, EMPFULL.txt and I need to split the data for every 30 records
and place a Typical Header as below with system and page number too.
2012.01.03 Employee Dept Report 1... (6 Replies)
All,
I currently have a requirement to fetch a Date value from a table. And then insert a Header record into a file along with that date value.
ex:
echo "HDR"" "`date +%Y%j` `date +%Y%m%d`
In the above example I used julian date and standard date using Current Date. But the requirement... (0 Replies)
I'm using a shell script to manipulate a data file. I have a large file with two sets of data samples (tracking memory consumption) taken over a long period of time, so I have many samples. The problem is that all the data is in the same file so that each sample contains two sets of data.... (2 Replies)
Discussion started by: abercrom
2 Replies
LEARN ABOUT V7
zgrep
ZGREP(1) General Commands Manual ZGREP(1)NAME
zgrep - search possibly compressed files for a regular expression
SYNOPSIS
zgrep [ grep_options ] [ -e ] pattern filename...
DESCRIPTION
Zgrep invokes grep on compressed or gzipped files. These grep options will cause zgrep to terminate with an error code:
(-[drRzZ]|--di*|--exc*|--inc*|--rec*|--nu*). All other options specified are passed directly to grep. If no file is specified, then the
standard input is decompressed if necessary and fed to grep. Otherwise the given files are uncompressed if necessary and fed to grep.
If the GREP environment variable is set, zgrep uses it as the grep program to be invoked.
EXIT CODE
2 - An option that is not supported was specified.
AUTHOR
Charles Levert (charles@comm.polymtl.ca)
SEE ALSO grep(1), gzexe(1), gzip(1), zdiff(1), zforce(1), zmore(1), znew(1)ZGREP(1)