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Bob Reeves · Guest

Hoping this is a good place to post this..

I am accessing image files from a USB Compact Flash card reader and need to
catch the error if a flash card isn't in the reader.

Here is what I am trying to do, please assume all variables have been
declared and initialized..

old_err_mode = SetErrorMode(SEM_FAILCRITICALERRORS);
SetLastError(-1);
dn = findfirst(FileName,&ffblk,0); // find first file
er = GetLastError();
if(er != -1) {
FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, 0, er, 0, buffer,
sizeof(buffer), 0);
ShowMsg("Unable to read Memory Card");
ShowMsg(buffer);
}
SetErrorMode(old_err_mode);

This works fine, catches the error and reports as expected, however if I
then insert a memory card into the reader and call the above code again it
gives me an invalid handle error. If I shut down and re-start the app it
will read the card without the error.

Looking like I missed re-setting something that will allow it to try to read
the drive the second time. Any ideas on what I need to do eliminate the
invalid handle error?

Thanks,
Bob

Mark Jacobs · Guest

"Bob Reeves" <bob (AT) somethinxtra (DOT) com> wrote in message
news:4638ae13$1 (AT) newsgroups (DOT) borland.com...

Bob Reeves · Guest

That worked like a charm.. I did discover that if I read it a 3rd time it
would work. This with the combination of your sugestion tells me the error
code wasn't being reset the second time through even though the code
assigns -1 to SetLast Error().

Must be something I don't understand about SetLast Error() but now it
doesn't matter.. It works, thanks you saved me allot of trouble. I was going
to loop through it twice to get around the problem but your solution is much
better.

Bob