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#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include "syscalls.h"
/* The C Programming Language: 2nd Edition
*
* Exercise 8-3: Design and write `_flushbuf`, `fflush`, and `fclose`.
*
* Notes: Not much guidance here, eh? :) We'll want to consult manpages.
*
* _flushbuf returns 0 on success, -1 on failure.
* fflush flushes a buffer, or *all* buffers
* fclose does housekeeping on _iob members so fds can be juggled
*
* Since work done in these exercises is predominantly in a header file, the
* final implementation is used for all exercises that rely on it. Attempts
* have been made to demonstrate *what* is being done, but it's difficult to do
* so without creating side effects inside the buffers themselves. Trust that
* if this file outputs its own source, everything is fine.
*/
int main() {
/* Let's copy 8-2's exercise but get a different look on the buffer. */
/* show the contents of buffers before and after flush */
FILE *fp = fopen("8-03_fflush-and-fclose.c", "r");
if (fp != NULL) {
char c;
while ((c = getc(fp)) != EOF) {
putchar(c);
}
/* fclose calls fflush */
fclose(fp);
fclose(stdout);
} else {
puts("Could not open file for reading.");
}
return 0;
}
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