Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Read not prompting/ pausing for input
Top Forums Shell Programming and Scripting Read not prompting/ pausing for input Post 302787455 by alister on Friday 29th of March 2013 03:16:34 PM
Old 03-29-2013
Quote:
Originally Posted by Cloudy_Cat
Code:
cat $1 | while read line; do 
    ...
    read ...
    ...
done

In case you are not aware, the redirections that affect the while-loop statement are inherited by all of the commands within it. So, in your case, the pipe between cat and while-read redirects the standard input of the entire while-loop to cat's output. Both of your read commands will be taking their input from cat. Line 1 from cat will be consumed by the first read statement. Line 2 from cat will be consumed by the second read statement, etc. Is that intentional? I assume it's not, since if that were the case, there would be no need to prompt cat for a response.

Regards,
Alister
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

pausing a script

hello all, I have a script (Solaris v8 ksh) monitoring an inbound directory for reports. The script will then capture the report based on a set of circumstances. However I am unable to capture a report larger then 2-Gig in size due to program limitations. What I need to do is pause the monitor... (6 Replies)
Discussion started by: gozer13
6 Replies

2. UNIX for Dummies Questions & Answers

Prompting for Input - Getting Undefined Variable

#!/bin/csh -f echo "Enter MEUPS User Id :-" read UID echo "You entered $UID" --------------------------------------- Whn executed, I get an error message "UID: Undefined variable" (1 Reply)
Discussion started by: Kartheg
1 Replies

3. Shell Programming and Scripting

read is not pausing to read

Can anyone tell me why this section of my script doesn't work? The script is designed to accept piped data, store it in a temporary location, and then prompt the user for their user name. It doesn't stop to read the username, however. It just finishes. It is called like: cat datafile | myscript... (3 Replies)
Discussion started by: davegerdt
3 Replies

4. UNIX for Dummies Questions & Answers

read input file

echo "enter employee #:/c" read employee grep -w $employee /tmp/file.txt when it asked me employee #, i typed employee, worked fine. when it asked me employee #, i type ENTER, it just sit there. if someone type in NULL or ENTER key, i want to exit out. (2 Replies)
Discussion started by: tjmannonline
2 Replies

5. Shell Programming and Scripting

Read input

I have a script. #! /bin/bash echo "Enter a word: " read word echo $word That outputs like this.. Enter a word: hello hello But how can i read on the same line the question is printed? Like this.. Enter a word: hello hello (2 Replies)
Discussion started by: cbreiny
2 Replies

6. Shell Programming and Scripting

Help with Bash piped while-read and a read user input at the same time

Hi I am new to writing script and want to use a Bash Piped while-read and read from user input. if something happens on server.log then do while loop or if something happend on user input then do while loop. Pseudocode something like: tail -n 3 -f server.log | while read serverline || read... (8 Replies)
Discussion started by: MyMorris
8 Replies

7. Shell Programming and Scripting

Read Input and go BG

My script needs to get some input from the user and go as a background process and run. I have something like read input. do while ... if .. fi done can i use nohup inside the script?? (7 Replies)
Discussion started by: Antergen
7 Replies

8. Shell Programming and Scripting

Read input files and merge them in given order and write them to input one param or one file

Dear Friends, I am looking for a shell script to merge input files into one file .. here is my idea: 1st paramter would be outfile file (all input files content) read all input files and merge them to input param 1 ex: if I pass 6 file names to the script then 1st file name as output file... (4 Replies)
Discussion started by: hyd1234
4 Replies

9. UNIX for Dummies Questions & Answers

Input for read command

Hello, I want to use the read command in order to input a keyword from the keyboard. I then want to use this keyword in a grep command. How to I input a phrase as a keyword? For example if I use read keyword "today is" and then use grep, I get "No such file or directory" error. (6 Replies)
Discussion started by: FelipeAd
6 Replies

10. Shell Programming and Scripting

Read input from Keyboard, do not proceed if no input

Hi, I am working on a script, which requests users to enter input. Ex: read -p "Please enter your email id:" email I don't want users skipping this entry, this has to be mandatory.I dont want to proceed without input. I can do a check if variable $email is empty and proceed if not.But, i... (7 Replies)
Discussion started by: aravindadla
7 Replies

LEARN ABOUT CENTOS

cat

CAT(1)								   User Commands							    CAT(1)

NAME

       cat - concatenate files and print on the standard output

SYNOPSIS

       cat [OPTION]... [FILE]...

DESCRIPTION

       Concatenate FILE(s), or standard input, to standard output.

       -A, --show-all
	      equivalent to -vET

       -b, --number-nonblank
	      number nonempty output lines, overrides -n

       -e     equivalent to -vE

       -E, --show-ends
	      display $ at end of each line

       -n, --number
	      number all output lines

       -s, --squeeze-blank
	      suppress repeated empty output lines

       -t     equivalent to -vT

       -T, --show-tabs
	      display TAB characters as ^I

       -u     (ignored)

       -v, --show-nonprinting
	      use ^ and M- notation, except for LFD and TAB

       --help display this help and exit

       --version
	      output version information and exit

       With no FILE, or when FILE is -, read standard input.

EXAMPLES

       cat f - g
	      Output f's contents, then standard input, then g's contents.

       cat    Copy standard input to standard output.

       GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report cat translation bugs to <http://translationproject.org/team/>

AUTHOR

       Written by Torbjorn Granlund and Richard M. Stallman.

COPYRIGHT

       Copyright (C) 2013 Free Software Foundation, Inc.  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO

       tac(1)

       The  full  documentation  for cat is maintained as a Texinfo manual.  If the info and cat programs are properly installed at your site, the
       command

	      info coreutils 'cat invocation'

       should give you access to the complete manual.

GNU coreutils 8.22						     June 2014								    CAT(1)
All times are GMT -4. The time now is 05:19 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy