Re: How can I check if a file exists in gawk?

On 3/27/2008 5:36 PM, Michael Jaritz wrote:
> Ed Morton schrieb:
> 
> 
>>>>>I'm writing an awk script that takes a path as a variable using -v.
In
>>>>>the BEGIN section I need to parse
>>>>>this file using:
>>>>
>>>>>while(getline < path)
>>>>>{
>>>>>:
>>>>>:
>>>>>}
>>>>
>>>>Why? There may be a better approach that doesn't involve getline.
>>>
>>>
>>>Why? Err , because I have to read in the file line by line to extract
>>>the fields to set up some mappings before I start processing the main
>>>file in the { } section.
>>
>>That does not mean you need to use getline in the BEGIN section. The
typical way
>>to do that instead is:
>>
>>awk '
>>NR==FNR{ "populate mappings"; next }
>>{ "main file processing" }
>>' mappingFile mainFile
> 
> 
> What is the typical way to do this if the both files needs different FS
> or different FIELDWIDTHS?

Set those variables between the files, e.g.:

awk '...' file1 FS='\t' file2

	Ed.