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Re: fork or printf problem

Sumit Rangawala forced the electrons to say:
> One thing i still couldn't understand is that  how printf distinguish
> between a terminal and a file.

The stdio code for printf might have something like: 

char buffer[BUFSIZ];
if (isatty (fileno (stdout)) {
      setvbuf (stdout, buffer, _IOLBUF, sizeof buffer);
} else {
      setvbuf (stdout, buffer, _IOFBUF, sizeof buffer);
/* Process the arguments to printf */

All the functions mentioned above have man pages. Read them.

> for it everything it has to do is to write to a file pointer ( fp = 1 )

The file pointer fp != 1. It is fileno (fp) == 1.

> How then the buffering changes with the type of file pointed by file
> pointer 1.

man isatty