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Bash: Insert in a variable a file


 
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# 1  
Bash: Insert in a variable a file

hi all
i have a problem in the bash shell. i'd like insert in a variable a file for example :

i have a file datafine.log in this file there is :
Code:
17/JUN/2019

i want to insert the value of datafine.log in a variable.
Regards
Frncesco

Moderator's Comments:
Mod Comment edit by bakunin: please use CODE-tags for your data as well as code. Thank you. And while you are at it, please don't write in two-word-lines. This is a question in a technical forum, not a poem.

Last edited by bakunin; 06-17-2019 at 10:57 AM..
# 2  
Quote:
Originally Posted by Francesco_IT
i have a file datafine.log in this file there is :
Code:
17/JUN/2019

i want to insert the value of datafine.log in a variable.
First, you should notice that funny things ca happen if the content of the file is more than the (probably expected) one line of text. Some caution is advised before you use data in this way therefore.

Aside from these considerations it is quite easy:

Code:
var=$( < /path/to/file )

$( .... ) is a subshell which runs the commands inside the brackets and puts it output on the line, similar to a variable expansion. The command < /path/to/file is a simple redirection which means the output is the content of the file.

I hope this helps.

bakunin
This User Gave Thanks to bakunin For This Post:
# 3  
Note that
Code:
var=$( < /path/to/file )

works in ksh, bash, zsh.
The standard shell needs a command like cat
Code:
var=$( cat < /path/to/file )

It is safer to only read one line from the file:
Code:
IFS= read -r var < /path/to/file

And this works in standard-compliant shells.
The IFS= and the -r force a raw read. By default read strips leading and trailing space and continues with the next line if the line ends with a \ character.

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