AIX

Hi all,

I have been struggling with this all day, and it is key to a conversion database I have to write.

The data converts the information out of an array using AWK, and basically all I have to do is figure out how to get the value of a variable inside a variable.

Right now at its simplest level, I have:


mpgw=13
CATEGORY=mpgw


I need to get the value 13 out of CATEGORY.



I have seen documentation that says you can do (within AWK):

findCATEGORY=eval echo CATEGORY

but this is just the same as:

findCATEGORY=CATEGORY

it is always mpgw, never 13. Does this make sense?
Perhaps it can be done within a function.
I would like to stay with AWK, or I have to start this conversion program completely over from scratch, and I've been working on it for days.

Thanks for any advice,

jeffpas


PS Perhaps a system call, writing and reading to an outside file, using a printf statement.............these are all things I'm investigating. But it has to be within the data stream (awk) so that it does it to every line being converted. No luck........

YMMV - dealing with multiple 'evals':

Code:

mpgw=13
CATEGORY=mpgw
Fred=CATEGORY

nawk -f jeff.awk myFile

jeff.awk:

Code:

BEGIN {
  FS=OFS="="
}
{ val[$1]=$2 }
{
  i=$2
  while (1) {
    if (i in val)
      i=val[i]
    else
      break
  }
}
$2=i

This looks like it could be the key to what I'm looking for, but it appears to be piping awk through a second file. I'm not quite understanding what you mean by your example.

Is there any way to do this with a function, within the AWK program?

I already have a conversion program written, it is quite lengthy, on an AIX box. I could replace the awk call with nawk, if I type nawk on the command line, it simply says awk. There is no man page available on this system. So, not sure if I have nawk or not.

Sorry...every brain cell available already firing. Not enough left over to wrap around this............

My examples is. well...... just an example -given a sample file you provided - how to convert it to what (I think) is needed.

Not having a complete data set nor a complete awk script - it's hard to say how to adjust a sample code above to your particular circumstance. You probably know all the details of what your awk script is doing the best - so you'll have massage the given code sample.

But...

Code:

BEGIN {
   FS=OFS="="
}
# the rest of the script


function evalVars(   i)
{
   val[$1]=$2
   i=$2
   while (1) {
      if (i in val)
        i=val[i]
      else
        break
    }
    $2=i
}

# some more of the script
#......

# some action here
{ 
   # resolve the vals
   evalVars()
  # do more stuff with the "resolved" data
  print
}

vgersh99,

I assume by your example you mean (for example):
in code:

>>
function recurse(i)
{
val[$1]=$2
i=$2
while (1) {
if ( i in val )
i = val[i]
else
break
}

$2=i
return i
}

Then further down in program, to get the value:

find_LOGCAT=recurse(LOGCAT)


>>>


So for example if you have (all in AWK):

mpgw=13 (this is a log category)
LOGCAT=mpgw (current category)

and want to know, what is the value of the current category?

in code, should be:
>>
find_LOGCAT=recurse(LOGCAT)
>>

Unfortunately, instead of pulling up 13 for every record that has 'mpgw', the awk output for LOGCAT is 14 and sometimes 15.........very odd.


Sorry, I indented everything, the forum seems to have removed all the formatting.
I am completely baffled by $1 and $2, don't understand this logic, but it appears to be at least pulling numbers at this point. Odd that I have no code 15, and that it isn't always the same number. But it should be 13.
not sure what the problem is.

hi,
look at the shell variables for the answer

try this link: http://sysunconfig.net/aixtips/ksh_tips.txt

Look at this:

====================

#!/bin/ksh

mpgw=13
CATEGORY=mpgw

CATEGORY2=$mpgw

echo $mpgw
echo $CATEGORY

echo $CATEGORY2
====================
Hope this help

It looks like I also have 'gawk' capability, and can use this instead.
Not sure what the difference is. Seems basically the same.