variable is not working in shell script

Question

I am using following in my shell script

LOGDATE='date +%m%d%y_%H%M'

and then calling same as following in the same shell script

$LOGDATE

but it is printing output as following

echo $LOGDATE

date +%m%d%y_%H%M

could anyone tell what am i doing wrong?

Are you trying to store the command `date +%m%d%y_%H%M` in the variable `LOGDATE`, or are you trying to execute the command and store its output in `LOGDATE`? — Gordon Davisson, May 30 '17 at 04:13

xvan · Accepted Answer · 2017-05-30T04:24:56.473

You've mistaken single quote character ', used for escaping strings (no variable is expanded, backslash doesn't escape character, and delimiters are ignored) for backtick character ` that executes the content in a subshell and returns stdout as a string.

LOGDATE=`date +%m%d%y_%H%M`

Newer bash versions also allow the syntax

LOGDATE=$(date +%m%d%y_%H%M)

It may be considered more readable and allows for easier nesting of expressions:

variable is not working in shell script

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