Re: Writing an int to a file, not quite sure how buffers work.

<mellyshum123@xxxxxxxx> wrote in message
Why don't you use fprintf?

--
Ian Collins.

Ok. I still don't know how the buffer works. Does it print out the
entire buffer or just the int I have placed in it?

Supposing I wrote:

fprintf(outputfile, "%d",buff);

C files come in binary or text flavours.
To write an integer to a binary file

fwrite(&x, sizeof(int), 1, fp);

This will write the bit pattern of the int to the file.

To do it in a machine-independent way

fputc( (x >> 8) & 0xFF, fp);
fputc( x & 0xFF, fp);

This will write a 16-bit big-endian integer to the file. Obviously you might
want to rewrite to make integers little-endian, or 32 bits.

Text files only understnad characters, almost always ASCII. So you have to
write the string "1234" to represent the integer 1234.
However fwrite(fp, "%d", x)) will do the conversion for you.

if you prefer you can write
char buff[64];
sprintf(buff, "%d", x);

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

using fprintf to write as a string.

Or you could use fwrite

fwrite(buff, 1, strlen(buff), fp);

There is not normally much point in doing this, unless you want your own
integer-to string conversion routine, for instance to write in binary rather
than decimal.
--
www.personal.leeds.ac.uk/~bgy1mm
freeware games to download.


.

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