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Top Forums Shell Programming and Scripting A better way to assign values to variables - shell Post 302916071 by Don Cragun on Saturday 6th of September 2014 02:29:49 PM
Old 09-06-2014
Quote:
Originally Posted by SkySmart
so i've been used to doing it this way:

Code:
SVAL=$(echo "7 3 2 38 3" | awk '{print $2}')
4VAL=$(echo "4:21:N:3" | awk -F":" '{print $4}')

I know there's a way to do it by putting the value in an array and assigning it that way. but i'm not sure how to do it efficiently. any ideas? i dont want to have to evoke two commands just to assign a variable. the two commands in this case being "echo" and "awk".

also, i'm hoping the proposed solutions can be used on all unix systems.

The shell i will be using in most cases is:

Code:
/bin/sh

What OS are you using? /bin/sh varies considerably from system to system. (It is a 1980's vintage Bourne shell on some systems, a hard link or a symlink to a Korn shell on some systems, a hard link or symliink to bash on some systems, and there are lots of other possibilities on other systems.)

And, 4val is not a valid variable name (at least in Bourne, bash, and Korn shells where user defined shell variables start with an underscore or an alphabetic character; not a number).

I don't understand why you're using echo and awk to get the 2nd and 4th fields from constant strings. If the strings are constants, why not just use:
Code:
VAL2=3
VAL4=3

So, if you aren't processing constant strings, where are they coming from? Are they already stored in a shell variable? Are they from the 1st line of a file?

Arrays can't be used on all UNIX systems with /bin/sh, but we can probably come up with something portable and efficient if you give us a better description of where the data comes from and what you want to do with it.

Last edited by Scrutinizer; 09-06-2014 at 03:42 PM..
 

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