file availability getline way

[visitnag]

Hi,

I am using getline to check whether input file is available or not.

The following is working fine:

Input file name: file<ym>

read -p "Enter month : " ym
awk 'BEGIN{

print getline < "file'$ym'" <0 ? "Not Available" : "Available"​

}'

but when i use the variable within awk its not working

awk 'BEGIN{
month=202303

print getline < "file"month <0 ? "Not Available" : "Available"​

}'

Please help
Thank you

 

[feherke]

Hi

Dumb thing as according to operator precedence should be fine, but in reality you have to add [highlight]parentheses[/highlight] :

awk '[b]BEGIN[/b][teal]{[/teal]
[navy]month[/navy][teal]=[/teal][purple]202303[/purple]
[b]print getline[/b] [teal]<[/teal] [highlight]([/highlight][i][green]"file"[/green][/i][navy]month[/navy][highlight])[/highlight] [teal]<[/teal][purple]0[/purple] [teal]?[/teal] [i][green]"Not Available"[/green][/i] [teal]:[/teal] [i][green]"Available"[/green][/i]
[teal]}[/teal]'

Feherke.
feherke.github.io

 

[visitnag]

Thank you very much!
Does this parenthesis syntax apply only when getline is used?

 

[feherke]

Hi

Maybe my memories are failing, as I can not reproduce it right now, but I have a feeling that also met it with [tt]print[/tt] when writing to file. But I would say on file/pipe input/output operations.


Feherke.
feherke.github.io