Please explain read in a while loop Post: 95493

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Top Forums Shell Programming and Scripting Please explain read in a while loop Post 95493 by jerardfjay on Wednesday 11th of January 2006 04:23:55 PM

01-11-2006

Registered User

Quote:

Originally Posted by bhargav

Code:

count=`wc -l file1 | tr -s " " | cut -d" " -f 2`
echo $count

while test $count -gt 0
do
    echo "Enter input :"
    read input
    echo $input
    ((count=count-1))
done

Bhargav,

I need to read input from user for every line that I read from the testfile. How would I accomplish that. Your example does not involve the loop reading from a file as well as reading user input within the loop of reading from a file. I use the $line variable within the loop to extract data that I require for other purposes.

Code:

while read line
do
    var1=$(echo "${line}" | awk -F "|" '{print $2}' | sed -e 's/^ *//g;s/ *$//g')
    read input?"Enter value :"      <<<---- This read does not work
    echo $input
#    do some processing with $var1 and $input and continue 
done < testfile

Any thoughts?
Jerardfjay

Last edited by jerardfjay; 01-11-2006 at 05:27 PM.. Reason: clarification of reply

jerardfjay

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LEARN ABOUT OSF1

line

line(1) 						      General Commands Manual							   line(1)

NAME

       line - Reads one line from standard input

SYNOPSIS

       line

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       line:  XCU5.0

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

OPTIONS

       None

DESCRIPTION

       The  line  command  copies one line, up to and including a newline, from standard input and writes it to standard output.  Use this command
       within a shell command file to read from your terminal.	The line command always writes at least a newline character.

NOTES

       The line utility has no internationalization features and is marked LEGACY in XCU Issue 5. Use the read utility instead.

EXIT STATUS

       Success.  End-of-File.

EXAMPLES

       To read a line from the keyboard and append it to a file, enter: echo 'Enter comments for the log:' echo ': c' line >>log

       This shell procedure displays the message: Enter comments for the log:

       It then reads a line of text from the keyboard and adds it to the end of the file log.  The echo  ':  c'  command  displays  a	:  (colon)
       prompt.	See the echo command for information about the c escape sequence.

SEE ALSO

       Commands:  echo(1), ksh(1), read(1), Bourne shell sh(1b), POSIX shell sh(1p)

       Functions:  read(2)

       Standards:  standards(5)

																	   line(1)

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