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Command output to a variable.


 
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# 1  
Old 12-14-2004
Question Command output to a variable.

With cut -c 8-13 myfile,

I am getting some numeric value.
In my shell script I am trying to assign something like this,
var=cut -c 8-13 myfile
But at the time of execution I am getting -c is not found.
If I dont assign, then script executes well.

Can we not simply use the value from one command output into the
variable in shell script?
# 2  
Old 12-14-2004
Instead of
var=cut -c 8-13 myfile
try
var=`cut -c 8-13 myfile`
# 3  
Old 12-14-2004
Meanwhile I started with awk. So on the similar lines I am trying to evaluate
awk o/p to var.

start=2
len=10
var=`awk <"$1""myfile" '{print substr($0,$start,$len)}'`
echo $var

After executing, I am getting awk error.

If at the place of $start & $len, I put 2 & 10 resp, it works.

Where am I making a mistake?
# 4  
Old 12-14-2004
What exactly is this line
Code:
var=`awk <"$1""myfile" '{print substr($0,$start,$len)}'`

supposed to be achieving?

Without knowing exactly what your problem is, something like
Code:
var=`awk -vs=$start -vl=$length '{print substr($0,s,l)}' filename`

may be more appropriate.

Cheers
ZB
# 5  
Old 12-15-2004
MySQL

Zazzybob

Yes,
that works. But let me explain what was my thought process behind prev command.

awk < filename - I understand as, file 'filename' is an input to awk. $1 param consists
dir loc where the file is residing.

In my fixed width file, I have these numeric values. Those I am retrieving with
substring.
# 6  
Old 12-15-2004
I know that that kind of redirection will work, but it's unneccessary - you can just take the filename onto the end of the command.

Cheers
ZB
# 7  
Old 12-15-2004
Also I would like to get rid of leading zeros, after I read a number from fixed width
file.
Say, 00000015 should be read as 15.

How would I achieve that?

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