help needed in fixing C programming error using cygwin !

Wed Dec 12 18:05:00 GMT 2001


I am sorry for this little email, I failed to find any help anywhere else so
I am sending it to you guyz.

I am calculating LRC character and appending it at end of a string. It works
fine, except when the character is null.
i.e.. when (int)lrc = 0

This string is to be send to a modem port and I cannot figure out how to do
it. I am using cygwin and gcc compiler for this program.

Sample: Say "xmessage" is a big string of size 216 which already contain
some ASCII data.
I calculate LRC character,
then create a new string,
append STX to the new string,
followed by xmessage and
at end I append storelrc.
Problem : When LRC int value is 0 (zero) it do not get appended to message.
Part of program is below.
/* Now define LRC character */
auto char lrc='a';
auto char storelrc[2]="";
int I;
/* calculate lrc */
for(lrc=xmessage[0], I=1; xmessage[i]; I++) lrc^=xmessage[i];
/* and copy the LRC stored in lrc to storelrc variable */
(void) sprintf(storelrc,"");
(void) sprintf(storelrc,"%c", lrc);
/* create send message */
auto char revmesg[96];
(void) sprintf(revmesg, "");
(void) sprintf(revmesg, "%c" , STX);
(void) strcat(revmesg,xmessage);
/* will not work if (int)lrc is zero */
(void) strcat(revmesg,storelrc);

I appreciate any suggestions. Please accept my apology if you find it off
the topic.


Also there is a feedback on cygwin from my experience. It looks great works
good. But for newbies the installer lay out is very confusing. When we start
installer and it shows the screen from where one can choose what all
packages we want to download, source code etc .. the options are very
confusing and it seems lot of stuff is put on one single screen. It needs
few hit and trial to figure out  how to change options. Also the cygwin
desktop icon can be made a little more "sexier", Now that I am fan of
cygwin, I want its icon to look better than windows icons ... LOL ;-) For
Redhat it should not be a big deal to improve the graphics of a tiny icon.
Thanks for listening.


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