🚀 go-pugleaf

In article <oylerb-2108950012310001@msp1-5.nas.mr.net>,
oylerb@tdkt.skypoint.net (Bill A. Oyler) wrote:

> Hello,
> 
> Back in my Pascal days, I had absolutely no problem writing strings
> (Str255s) to text files.  I would just do something like this:
> 
>         TextToWrite := 'hello, world!';
>         Count := Length(TextToWrite) - 1;
>         OSError := SetFPos(LogFileRefNum, fsFromLEOF, 0);
>         OSError := FSWrite(LogFileRefNum, Count, @TextToWrite[1]);
> 
> What would be the C equivalent of this code??
> 
> Asside from the obvious syntax differences, all I changed was
> "@TextToWrite[1]" to "&TextToWrite + 1".  Is there something more I need
> to do?  I keep getting garble in my text file....
> 
> Thanks!!
> 

Try:
 ...
 OSError = SetFPos(LogFileRefNum, fsFromLEOF, 0);
 OSError = FSWrite(LogFileRefNum, Count,(Ptr) &(TextToWrite[1]));
 ...

this should work, also i didn't try it


Gulpi
= Martin Adler

In article <oylerb-2108950012310001@msp1-5.nas.mr.net>,
oylerb@tdkt.skypoint.net (Bill A. Oyler) wrote:

> Hello,
> 
> Back in my Pascal days, I had absolutely no problem writing strings
> (Str255s) to text files.  I would just do something like this:
> 
>         TextToWrite := 'hello, world!';
>         Count := Length(TextToWrite) - 1;
>         OSError := SetFPos(LogFileRefNum, fsFromLEOF, 0);
>         OSError := FSWrite(LogFileRefNum, Count, @TextToWrite[1]);
> 
> What would be the C equivalent of this code??
> 
> Asside from the obvious syntax differences, all I changed was
> "@TextToWrite[1]" to "&TextToWrite + 1".  Is there something more I need
> to do?  I keep getting garble in my text file....
> 
> 
> Try:
>  ...
>  OSError = SetFPos(LogFileRefNum, fsFromLEOF, 0);
>  OSError = FSWrite(LogFileRefNum, Count,(Ptr) &(TextToWrite[1]));
>  ...
> 
> this should work, also i didn't try it

Sorry for "also", it was my f.. english!

your version "&TextToWrite + 1" didn't work because in C the var
"TextToWrite" is the pointer to the pascal-string. So, your assignment
"&TextToWrite" is an ptr to a ptr to the pascal-string, this can't work.
for details, you should read the pointer/array-chapter of any c-book.

the following line should be equivalent:

OSError = FSWrite(LogFileRefNum, Count,(Ptr) &(TextToWrite[1]));
OSError = FSWrite(LogFileRefNum, Count,(Ptr) (TextToWrite + 1));

(i like to write more brackets and typecoercing than really needed, but i
think this makes the code more readable)



Gulpi
= Martin Adler

In article <adler-2108951328000001@138.244.207.201> adler@informatik.tu-muenchen.de (Martin Adler) writes:
>In article <oylerb-2108950012310001@msp1-5.nas.mr.net>,
>> Back in my Pascal days, I had absolutely no problem writing strings
>> (Str255s) to text files.  I would just do something like this:
>> 
>>         TextToWrite := 'hello, world!';

<snip>

>the following line should be equivalent:

>OSError = FSWrite(LogFileRefNum, Count,(Ptr) &(TextToWrite[1]));
>OSError = FSWrite(LogFileRefNum, Count,(Ptr) (TextToWrite + 1));

<snip>

Assuming that the assignment above was translated into C as 

         TextToWrite = "hello, world!";

you are passing FSWrite() as it's third parameter a pointer to the string
"ello, world!". Are you _sure_ that's what you want?

Lose the [1] or + 1, which means also lose the & and the parens.  Adding one 
may have been necessary in Pascal because of the count byte in the string.  C 
doesn't have one.

Regards,
jpc

John Caulfield
johnpc@omni.voicenet.com

Don't put that in your mouth.  You 
don't know where it's been. - Your mother

In article <johnpc.39.075ECBAC@omni.voicenet.com>,
johnpc@omni.voicenet.com (John Caulfield) wrote:

> In article <adler-2108951328000001@138.244.207.201>
adler@informatik.tu-muenchen.de (Martin Adler) writes:
> >In article <oylerb-2108950012310001@msp1-5.nas.mr.net>,
> >> Back in my Pascal days, I had absolutely no problem writing strings
> >> (Str255s) to text files.  I would just do something like this:
> >> 
> >>         TextToWrite := 'hello, world!';
> 
> <snip>
> 
> >the following line should be equivalent:
> 
> >OSError = FSWrite(LogFileRefNum, Count,(Ptr) &(TextToWrite[1]));
> >OSError = FSWrite(LogFileRefNum, Count,(Ptr) (TextToWrite + 1));
> 
> <snip>
> 
> Assuming that the assignment above was translated into C as 
> 
>          TextToWrite = "hello, world!";
> 
> you are passing FSWrite() as it's third parameter a pointer to the string
> "ello, world!". Are you _sure_ that's what you want?
> 
> Lose the [1] or + 1, which means also lose the & and the parens.  Adding one 
> may have been necessary in Pascal because of the count byte in the string.  C 
> doesn't have one.
> 
> Regards,
> jpc
> 

ok, ok, ...
i didn't realize exactly the "TextToWrite := 'hello, world!';"-line, so
you're right, my solution is only right for a pascal-string. i only looked
at the header:  
> >> Back in my Pascal days, I had absolutely no problem writing strings
> >> (Str255s) to text files.  I would just do something like this:

correct solution:

...
 OSErr   OSError;
 char    TextToWrite[14] = 'hello, world!'; // 14 = 13 chars from 'hello,
world!' + 1 char delimiter
 long    Count = strlen(TextToWrite);
 
 OSError = SetFPos(LogFileRefNum, fsFromLEOF, 0);
 OSError = FSWrite(LogFileRefNum, Count, TextToWrite);

or if TextToWrite is a pascal-string (often returned by toolbox-routines):

...
 OSErr   OSError;
 long    Count = TextToWrite[0];

OSError = SetFPos(LogFileRefNum, fsFromLEOF, 0);
OSError = FSWrite(LogFileRefNum, Count,(Ptr) (TextToWrite + 1));

now i hope it's ok...

Gulpi
= Martin Adler