Top Forums UNIX for Beginners Questions & Answers How do I assign the output of a command to a variable within a loop in bash? Post 303033974 by Don Cragun on Monday 15th of April 2019 12:48:59 PM
Please show us your entire script instead of showing us one line at a time.

It seems highly likely that you are setting the variable you want inside a sub-shell and that makes the assigned value invisible outside of that sub-shell. But we can't know that until we can see all of your code.
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OPEN(1) 							     Linux 1.x								   OPEN(1)

NAME
open - start a program on a new virtual terminal (VT). SYNOPSIS
open [-c vtnumber] [-s] [-u] [-l] [-v] [--] command command_options DESCRIPTION
open will find the first available VT, and run on it the given command with the given command options, standard input, output and error are directed to that terminal. The current search path ($PATH) is used to find the requested command. If no command is specified then the envi- ronment variable $SHELL is used. OPTIONS -c vtnumber Use the given VT number and not the first available. Note you must have write access to the supplied VT for this to work. -s Switch to the new VT when starting the command. The VT of the new command will be made the new current VT. -u Figure out the owner of the current VT, and run login as that user. Suitable to be called by init. Shouldn't be used with -c or -l. -l Make the command a login shell. A - is prepended to the name of the command to be executed. -v Be a bit more verbose. -w wait for command to complete. If -w and -s are used together then open will switch back to the controlling terminal when the command completes. -- end of options to open. NOTE
If open is compiled with a POSIX (Gnu) getopt() and you wish to set options to the command to be run, then you must supply the end of options -- flag before the command. EXAMPLES
open can be used to start a shell on the next free VT, by using the command: open bash To start the shell as a login shell, use: open -l bash To get a long listing you must supply the -- separator: open -- ls -l SEE ALSO
login(1), doshell(8), switchto(1). AUTHOR
Jon Tombs <jon@gtex02.us.es or jon@robots.ox.ac.uk> -w idea from "sam". 19 Jul 1996 V1.4 OPEN(1)

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