Reading from a file and storing it in a variable


 
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# 1  
Old 09-23-2010
Reading from a file and storing it in a variable

Hi folks,
I'm using bash and would like to do the following. I would like to read some values from the file and store it in the variable and use it.

My file is 1.txt and its contents are

VERSION=5.6
UPDATE=4




I would like to read "5.6" and "4" and store it in a variable in shell script. How do I do that?

Thanks,
# 2  
Old 09-23-2010
You can use: eval $(<file)
# 3  
Old 09-23-2010
Quote:
Originally Posted by danmero
You can use: eval $(<file)
I don't understand this though. How do I search for patterns in a text file and read the whole line in shell script?
# 4  
Old 09-23-2010
Code:
# cat file
VERSION=5.6
UPDATE=4

# cat script.sh
#!/bin/bash -x
eval $(<file)
echo ${VERSION} ${UPDATE}

# /temp/script.sh
+ eval VERSION=5.6 UPDATE=4
++ VERSION=5.6
++ UPDATE=4
+ echo 5.6 4
5.6 4

# 5  
Old 09-23-2010
Can any one help, why my code is not right?

Code:
IFS="="
while read key value
do
  $key=$value
done < 1.txt


Last edited by rdcwayx; 09-24-2010 at 12:12 AM..
# 6  
Old 09-23-2010
Quote:
Originally Posted by rdcwayx
Can any one help, why it is not right?

Code:
IFS="="
while read key value
do
  $key=$value
done < 1.txt

That's correct, however my previous solution will do exactly the same
Code:
eval $(<file)

# 7  
Old 09-23-2010
Quote:
Originally Posted by rdcwayx
Code:
$key=$value

variables are declared like this
Code:
 key=$value

however, since they are taken from file, you can use declare (instead of eval , which is dangerous in some cases)
Code:
 while IFS== read -r key value do declare $key=$value done


Last edited by kurumi; 09-24-2010 at 12:06 AM..
This User Gave Thanks to kurumi For This Post:
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