Sponsored Content
Top Forums Shell Programming and Scripting Problem with while loop reading every line of a text file Post 302949222 by neutronscott on Wednesday 8th of July 2015 09:12:43 AM
Old 07-08-2015
both of these read operations work on the same stdin. you need to assign to a different fd and use that for one of them. the easiest way to do this is to ditch the useless use of cat (uuoc award).

Code:
while read line <&9; do
  echo "$line"
  echo "press enter key"
  read
done 9<passwd_sample

Now we redirect passwd_sample into fd 9 for the entire while block, yet only the first read operation operates on fd 9. in this way, we'll keep our position in the file with each iteration and read line-by-line but not interfere with the read that wants input from the terminal.

if you're using bash, you can use read -s -N 1 for grabbing a single key. otherwise you'll need to press enter rather than "any" key.
These 3 Users Gave Thanks to neutronscott For This Post:
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

reading text file line by line

Ok. before anyone mentions it, I did search for this but I'm not sure if I am looking for the right thing. Now, onto my issue. I have been keeping vmstats output in running text files. So I have a file that looks like this: vmstat 2 5 2005.09.19 kthr memory page ... (6 Replies)
Discussion started by: MizzGail
6 Replies

2. Shell Programming and Scripting

Reading data from a specific line in a text file

hello, I have got the following problem that I am hoping someone can help with please. 1. I have got the following text file (below) , the columns data are 'Test Day', 'Board', 'Betting Number'. TEXT FILE ============================================ 1 3 02-01-27-28-29-30 0 1... (1 Reply)
Discussion started by: jermaine4ever
1 Replies

3. Shell Programming and Scripting

Reading data from a specific line in a text file

Hello, I have a problem which is giving me headache for days, can some please help. Please see code and text fiel below. Please see text in red for the problem I am facing # Program gets an input x from user while read line ; do echo... (4 Replies)
Discussion started by: jermaine4ever
4 Replies

4. Shell Programming and Scripting

[Solved] Problem in reading a file line by line till it reaches a white line

So, I want to read line-by-line a text file with unknown number of files.... So: a=1 b=1 while ; do b=`sed -n '$ap' test` a=`expr $a + 1` $here do something with b etc done the problem is that sed does not seem to recognise the $a, even when trying sed -n ' $a p' So, I cannot read... (3 Replies)
Discussion started by: hakermania
3 Replies

5. Shell Programming and Scripting

Problem reading file in while/read loop

I know I should be able to see a way of doing this easily, but my brain just won't engage. I have a script working on an embedded device that checks to see if an item is in a blacklist before performing some actions. At the moment the code reads thus.... while read BLACKLIST ; do ... (7 Replies)
Discussion started by: Bashingaway
7 Replies

6. Shell Programming and Scripting

reading line by line from a text file

Hi, I have a text file something like this: 10.10.10.1, ldap, cn=users,dc=example,dc=com ..... ... and many more lines ... ... now i want to read each individual line from the file and assign it to a variable example: the script should read 10.10.10.1 and assign it to a variable say... (3 Replies)
Discussion started by: sunrexstar
3 Replies

7. Shell Programming and Scripting

Read file using while loop not reading last line

I have written a script to read the file line by line. It is reading and printing the lines. But it is coming out of loop before reading last line. So I am not able to print last line. How do I solve it. (6 Replies)
Discussion started by: dgmm
6 Replies

8. Shell Programming and Scripting

While loop is not reading next line in the file when IF condition is used.

Hi Guys I am new to scripting.Please forgive for asking basic questions. I want to write a script to check whether the logs are getting updated in last 15 mins. cat server 192.168.1.6 192.168.1.7 cat list 192.168.1.7 /logs/logpath1 192.168.1.7 /logs/logpath2 192.168.1.6... (4 Replies)
Discussion started by: vdurai
4 Replies

9. Shell Programming and Scripting

Reading text file, comparing a value in a line, and placing only part of the line in a variable?

I need some help. I would like to read in a text file. Take a variable such as ROW-D-01, compare it to what's in one line in the text file such as PROD/VM/ROW-D-01 and only input PROD/VM into a variable without the /ROW-D-01. Is this possible? any help is appreciated. (2 Replies)
Discussion started by: xChristopher
2 Replies

10. Shell Programming and Scripting

Reading line by line from live log file using while loop and considering only those lines start from

Hi, I want to read a live log file line by line and considering those line which start from time stamp; Below code I am using, which read line but throws an exception when comparing line that does not contain error code tail -F /logs/COMMON-ERROR.log | while read myline; do... (2 Replies)
Discussion started by: ketanraut
2 Replies
IO::All::HTTP(3pm)					User Contributed Perl Documentation					IO::All::HTTP(3pm)

NAME
IO::All::LWP - Extends IO::All to HTTP URLs SYNOPSIS
use IO::All; $content < io('http://example.org'); # GET webpage into scalar io('http://example.org') > io('index.html'); # GET to file "hello " > io('http://example.org/index.html'); # PUT webpage # two ways of getting a page with a password: $content < io('http://me:secret@example.org'); $content < io('http://example.org')->user('me')->password('secret'); DESCRIPTION
This module extends IO::All for dealing with HTTP URLs. Note that you don't need to use it explicitly, as it is autoloaded by IO::All whenever it sees something that looks like an HTTP URL. The SYNOPSIS shows some simple typical examples, but there are many other interesting combinations with other IO::All features! For example, you can get an HTTP URL and write the content to a socket, or to an FTP URL, of to a DBM file. METHODS
This is a subclass of IO::All::LWP. The only new method is "http", which can be used to create a blank IO::All::HTTP object; or it can also take an HTTP URL as a parameter. Note that in most cases it is simpler just to call io('http://example.com'), which calls the "http" method automatically. OPERATOR OVERLOADING
The same operators from IO::All may be used. < GETs an HTTP URL; > PUTs to an HTTP URL. SEE ALSO
IO::All, IO::All::LWP, LWP. AUTHORS
Ivan Tubert-Brohman <itub@cpan.org> and Brian Ingerson <ingy@cpan.org> COPYRIGHT
Copyright (c) 2007. Ivan Tubert-Brohman and Brian Ingerson. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See <http://www.perl.com/perl/misc/Artistic.html> perl v5.10.0 2007-03-29 IO::All::HTTP(3pm)
All times are GMT -4. The time now is 03:09 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy