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Full Discussion: Shell script use two variable in for loop
Top Forums Shell Programming and Scripting Shell script use two variable in for loop Post 303027582 by Corona688 on Wednesday 19th of December 2018 12:23:14 PM
Old 12-19-2018
The 'while read' loop is better in almost every way. It avoids the waste of using cat, and doesn't have the unfortunate side-effects of working behind a pipe (variable changes not preserved in most shells).

Code:
while read USERNAME COMMENT
do
        echo "USERNAME=$USERNAME, comment=$COMMENT"
done < inputfile

You can change the delimiter by changing the IFS variable, i.e. IFS=":" read var1 var2 var3
 

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LEARN ABOUT DEBIAN

id

ID(1)								   User Commands							     ID(1)

NAME

       id - print real and effective user and group IDs

SYNOPSIS

       id [OPTION]... [USERNAME]

DESCRIPTION

       Print user and group information for the specified USERNAME, or (when USERNAME omitted) for the current user.

       -a     ignore, for compatibility with other versions

       -Z, --context
	      print only the security context of the current user

       -g, --group
	      print only the effective group ID

       -G, --groups
	      print all group IDs

       -n, --name
	      print a name instead of a number, for -ugG

       -r, --real
	      print the real ID instead of the effective ID, with -ugG

       -u, --user
	      print only the effective user ID

       --help display this help and exit

       --version
	      output version information and exit

       Without any OPTION, print some useful set of identified information.

AUTHOR

       Written by Arnold Robbins and David MacKenzie.

REPORTING BUGS

       Report id bugs to bug-coreutils@gnu.org
       GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
       General help using GNU software: <http://www.gnu.org/gethelp/>
       Report id translation bugs to <http://translationproject.org/team/>

COPYRIGHT

       Copyright (C) 2011 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

       The full documentation for id is maintained as a Texinfo manual.  If the info and id programs are properly installed at your site, the com-
       mand

	      info coreutils 'id invocation'

       should give you access to the complete manual.

GNU coreutils 8.12.197-032bb					  September 2011							     ID(1)
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