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Full Discussion: Loop iteration with two variables
Top Forums Shell Programming and Scripting Loop iteration with two variables Post 302978554 by MadeInGermany on Monday 1st of August 2016 08:44:59 AM
Old 08-01-2016
The post#12 does not work with an old Bourne shell
Code:
/tmp/sh37022: cannot open

Maybe a bug? The shell seems to remember the file name, not the handle.
This modification makes it work:
Code:
#!/bin/sh
group1="/usr/version1/cmd /usr/version1/properties"
group2="/usr/version2/cmd /user/version2/properties"

printf "%s\n" $group1 |
while read name1 && read name2 <&3
do
  echo "$name1" "$name2"
done 3<<EOF
`printf "%s\n" $group2`
EOF

The previous post can easily feed a while loop
Code:
#!/bin/sh
group1="/usr/version1/cmd /usr/version1/properties"
group2="/usr/version2/cmd /user/version2/properties"

printf "%s\n" $group1 $group2 | pr -t2 |
while read name1 name2
do
  echo "$name1" "$name2"
done

 

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LEARN ABOUT OPENSOLARIS

shells

shells(4)							   File Formats 							 shells(4)

NAME

       shells - shell database

SYNOPSIS

       /etc/shells

DESCRIPTION

       The shells file contains a list of the shells on the system. Applications use this file to determine whether a shell is valid. See getuser-
       shell(3C). For each shell a single line should be present, consisting of the shell's path, relative to root.

       A hash mark (#) indicates the beginning of a comment; subsequent characters up to the end of the line are not interpreted by  the  routines
       which search the file. Blank lines are also ignored.

       The following default shells are used by utilities: /bin/bash, /bin/csh, /bin/jsh, /bin/ksh, /bin/ksh93, /bin/pfcsh, /bin/pfksh, /bin/pfsh,
       /bin/sh, /bin/tcsh, /bin/zsh, /sbin/jsh, /sbin/sh, /usr/bin/bash, /usr/bin/csh, /usr/bin/jsh, /usr/bin/ksh, /usr/bin/ksh93, /usr/bin/pfcsh,
       /usr/bin/pfksh, /usr/bin/pfsh, and /usr/bin/sh, /usr/bin/tcsh, /usr/bin/zsh, and /usr/sfw/bin/zsh. /etc/shells overrides the default list.

       Invalid shells in /etc/shells could cause unexpected behavior, such as being unable to log in by way of ftp(1).

FILES

       /etc/shells    list of shells on system

SEE ALSO

       vipw(1B), ftpd(1M), sendmail(1M), getusershell(3C), aliases(4)

SunOS 5.11							    20 Nov 2007 							 shells(4)
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