Text files driving me mad

Sarah sarahr at genesearch.com.au
Tue Jun 4 17:17:01 CDT 2002


Hi Bill,

I haven't done any of this myself, but I wonder would the CRLF constant 
be any use to you?

If you check the Transcript dictionary entry for CR, down the bottom you 
will see this:
"The line feed character is the standard end-of-line delimiter on Unix 
systems. The end-of-line delimiter for Mac OS systems is a carriage 
return, and the end-of-line delimiter for Windows systems is a carriage 
return followed by a line feed."

I found it slightly confusing that CR (return) and linefeed are both 
ASCII 10, while CRLF is ASCII 13 + ASCII 10. I would have expected CR to 
be ASCII 13 and linefeed to be ASCII 10. The dictionary entry makes a 
distinction between Unix linefeed and Mac carriage return but in 
Transcript linefeed = cr, so I am assuming that Unix uses ASCII 10 and 
Mac uses ASCII 13.

Here (in pseudo-code) is what it seems to need:
if system = Windows then
	replace CR with CRLF
	replace ASCII 13 with CRLF
else if system = Mac then
	replace CR with ASCII 13
	replace CRLF with ASCII 13
else if system = Unix (& this probably includes Mac OS X) then
	replace ASCII 13 with CR
	replace CRLF with CR
end if

This is certainly an interesting and important topic, so I will wait to 
see how you solve it in the end. It has been very instructive for me to 
have a look at this as I had assumed that (as in Hypercard) linefeed was 
ASCII 10 and return (or CR) was ASCII 13.

Cheers,
Sarah

On Wednesday, June 5, 2002, at 01:44  AM, Bill Vlahos wrote:

> I'm still having fits over reading in a text file for processing by 
> various platforms. There has to be a better way.
>
> If I get URL (http:...text file) each platform brings in a line feed 
> only text file correctly. I don't have to do anything on Mac, Win, 
> Linux, or Solaris.
>
> If I get URL (file:...text file) I get various results depending on 
> which platform as it sees and knows what to do with cr, lf, or crlf. My 
> file is currently cr delimited which works fine with Macs and Windows 
> but not with Linux. I put in an option to replace cr with lf but it 
> doesn't seem to work with Linux. In looking at the Rev docs "return" is 
> a synonym for "lf" so perhaps that is my problem. I will try it today 
> with replacing ASCII 13 instead of "return". However, all of this seems 
> like a hack when the get URL http works all by itself.
>
> Is there a way to have the get URL file command to behave like the get 
> URL http command or is this a function of the web server doing the 
> right thing?
>
> Thanks,
> Bill Vlahos
>
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