End of File/constant char

[gonzilla]

Hi,

I feel like I should know why this is happening...but I'm not sure why. I work on Sun UNIX machine. I am trying to simply write a file with a character array using
fprintf(). Like this...

FILE *fp;
char array[]="this is the output string";

open the file (tried text and binary)...

fprintf(fp, array);
fclose(fp);

...or I have tried other versions of that fprintf() statement...

fprintf(fp, "%s" , array);
etc...

When I use vi to open the file, it looks fine but I get a prompt saying incomplete last line. The only version of the fprintf() that doesn't produce that prompt is

fprint(fp, "%s\n", array);

Why do I need the newline? Why does that fix it? I'm guessing it flushes the line, but doesn't fclose(fp) do that already? I feel like theremust be another way. I even put a newline at the end of the array string and that didn't work, ie..

char array[]="this is the output string\n";

Any help would be appreciated.

Thanks.

-Tyler

 

[rwb1959]

vi recognizes "\n" as end-of-line. There's nothing actually wrong
with the text file.

 

[DZH]

The call:

      fprintf(fp, "%s" , array);

writes the text without adding an end-of-line (EOL) marker, which is '\n' or '\r\n' (for DOS/Windows). A line is a sequence of characters terminated by the EOL marker. Every file is terminated by an end-of-file (EOF) marker which is usually -1. The text in the file, after the above fprintf call, is as follows:

       this is the output stringEOF

Whereas vi expects it to be:

       this is the output stringEOLEOF

The first line is not terminated properly, even though most well-written text utilities are able to pick this up. It's good thing that vi warns you of this scenario.

 

[gonzilla]

Thank you for the clarification! That makes tons of sense.

Thanks.

-Tyler