One of the better tools to use in this instance would be awk. The below example does not need grep or cat (cat is very rarely used at all in most situations), it will print field 7 and the number of fields:
Last edited by pilnet101; 06-09-2015 at 03:50 PM..
Is there a way to count the no. of fields (columns) in a file?
Actually I need to cut some fields starting from the middle to the end. How can I specify to cut till last field?
thanks in advance
:) (4 Replies)
I want to cut two coloums simulatiously and paste in some other file
for ex:
cut d ' ' -f3 -f4 xxx | paste yyy - > zzz;
from the above i want to cut two fileds 3 and 4 and paste as last coloums of single file (zzz).
how to solve this
regards
rajan (1 Reply)
I have a tab delimited file which has 90 fields and 15 million rows approximately...
I need to cut the first 78 fields only and I am using the
cut -f1-78 <filename> <outputfile>
It is taking a lot of time...
Is there a faster way of doing this? Can we use NAWK to gain better... (0 Replies)
I have a text:
dsj khfksjdh <time> EST 2006
ab cgnr jkkjt <time> EST 2006
gfhdgjghg <time> EST 2006
fkdjh kjhsekjrh kdjhfkh jhdfkhfdkjh kjdf <time> EST 2006
In the above file i need to extract time from every line... which is always the third from the last... Pls help!
Cheers,
Bouren (4 Replies)
Hello,
I would like to extract one or two fields of a line.
At the moment, I am extracting the first field of a line:
command | cut -f 1 -d '.' > file
The line can have two or three fields delimited with a dot.
if three fields, I want to be able to get the first two
ie if line =... (3 Replies)
I'm working on formatting some attendance data to meet a vendors requirements to upload to their system. With some help on the forums here, I have the data close. But they've since changed what they want.
The vendor wants me to submit three fields to them. Field 1 is the studentid field,... (4 Replies)
Hi,
I have data in following format.
10001, John, Daves, Architecture, -2219
10002, Jim, Cirners, Businessman, -2219
1003, Tom, Katch, Engineer, -14003
I want to select the last column of the above given file and paste it on a different file in the following manner.
File TEST column... (11 Replies)
Hello All,
I got a requirement when I was working with a file. Say the file has unloads of data from a table in the form
1|121|asda|434|thesi|2012|05|24|
1|343|unit|09|best|2012|11|5|
I was put into a scenario where I need the field count in all the lines in that file. It was simply... (6 Replies)
I'm having bother getting both lines contained in a file to output as the same value.
A simple example:
john:123456:123:456:doe
john:123456:123:doe
cut -d: -f1,4 input file
john:456
john:doe ^ first line should be same as second.
trick one for me, i know why it's because of the... (4 Replies)
I'm a complete beginner in UNIX (and not a computer science student either), just undergoing a tutoring course. Trying to replicate the instructions on my own I directed output of the ls listing command (lists all files of my home directory ) to My_dir.tsv file (see the screenshot) to make use of... (9 Replies)
Discussion started by: scrutinizerix
9 Replies
LEARN ABOUT DEBIAN
expect_unbuffer
UNBUFFER(1) General Commands Manual UNBUFFER(1)NAME
unbuffer - unbuffer output
SYNOPSIS
unbuffer program [ args ]
INTRODUCTION
unbuffer disables the output buffering that occurs when program output is redirected from non-interactive programs. For example, suppose
you are watching the output from a fifo by running it through od and then more.
od -c /tmp/fifo | more
You will not see anything until a full page of output has been produced.
You can disable this automatic buffering as follows:
unbuffer od -c /tmp/fifo | more
Normally, unbuffer does not read from stdin. This simplifies use of unbuffer in some situations. To use unbuffer in a pipeline, use the
-p flag. Example:
process1 | unbuffer -p process2 | process3
CAVEATS
unbuffer -p may appear to work incorrectly if a process feeding input to unbuffer exits. Consider:
process1 | unbuffer -p process2 | process3
If process1 exits, process2 may not yet have finished. It is impossible for unbuffer to know long to wait for process2 and process2 may
not ever finish, for example, if it is a filter. For expediency, unbuffer simply exits when it encounters an EOF from either its input or
process2.
In order to have a version of unbuffer that worked in all situations, an oracle would be necessary. If you want an application-specific
solution, workarounds or hand-coded Expect may be more suitable. For example, the following example shows how to allow grep to finish pro-
cessing when the cat before it finishes first. Using cat to feed grep would never require unbuffer in real life. It is merely a place-
holder for some imaginary process that may or may not finish. Similarly, the final cat at the end of the pipeline is also a placeholder
for another process.
$ cat /tmp/abcdef.log | grep abc | cat
abcdef
xxxabc defxxx
$ cat /tmp/abcdef.log | unbuffer grep abc | cat
$ (cat /tmp/abcdef.log ; sleep 1) | unbuffer grep abc | cat
abcdef
xxxabc defxxx
$
BUGS
The man page is longer than the program.
SEE ALSO
"Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Programs" by Don Libes, O'Reilly and Associates, January 1995.
AUTHOR
Don Libes, National Institute of Standards and Technology
1 June 1994 UNBUFFER(1)