Double variable -- I think

[jdh239]

I don't really know much about programming/scripting that much. I had one programming class once. I am trying to get the following to work, but it only works with numerical numbers, and fails with text. How can I get the text portion to work?:

 #!/bin/bash
 
LARGE_FILE_MAX_SIZE=5
LARGE_FILE_TYPE=GB
 
convert_data (){
        CONVERT_TYPE=$((${1}_FILE_TYPE))
        CONVERT_TOTAL=$((${1}_FILE_MAX_SIZE))
        echo CONVERT_TYPE:  $CONVERT_TYPE
        echo CONVERT_TOTAL: $CONVERT_TOTAL
}
 
convert_data LARGE 
  

The above returns the following:
# ./data_gen.sh
CONVERT_TYPE: 0 <--- I need this to read GB (or whatever string is passed in)
CONVERT_TOTAL: 5

Thanks in advance for your help

BTW: I am not a student and this isn't homework. It is a script I am trying to refine that will generate large amounts of custom data for some of the testing I have to do. My current script generates the data, but I am refining it to give me more control of the size of data it will generate (this is only a small portion of the overall script)

[nmset]

#!/bin/bash 
 
LARGE_FILE_MAX_SIZE=2
LARGE_FILE_TYPE=GB 
 
convert_data (){ 
        CONVERT_TYPE=${1}_FILE_TYPE
        CONVERT_TOTAL=$((${1}_FILE_MAX_SIZE))
        echo CONVERT_TYPE:  ${!CONVERT_TYPE}
        echo CONVERT_TOTAL: $CONVERT_TOTAL
} 
 
convert_data LARGE

CONVERT_TYPE=$((${1}_FILE_TYPE))

will always returm 0 as the resulting variable contains a non numeric value.

${1}_FILE_TYPE

becomes the the value "LARGE_FILE_TYPE" contained in "CONVERT_TYPE"

${!CONVERT_TYPE}

is bash's variable indirection. "LARGE_FILE_TYPE" is used as a variable in itself and points to it's content : GB

[jdh239]

NICE! Thank you very much. I don't quite understand what you said, but I see that it works. I work with a guy that can explain what you did to me.

Thank you.