nonblockw.c

unix高级编程源代码.<<unix高级编程>>

#include	<sys/types.h>
#include	<errno.h>
#include	<fcntl.h>
#include	"ourhdr.h"

char	buf[100000];

int
main(void)
{
	int		ntowrite, nwrite;
	char	*ptr;

	ntowrite = read(STDIN_FILENO, buf, sizeof(buf));
	fprintf(stderr, "read %d bytes\n", ntowrite);

	set_fl(STDOUT_FILENO, O_NONBLOCK);	/* set nonblocking */

	for (ptr = buf; ntowrite > 0; ) {
		errno = 0;
		nwrite = write(STDOUT_FILENO, ptr, ntowrite);
		fprintf(stderr, "nwrite = %d, errno = %d\n", nwrite, errno);
		if (nwrite > 0) {
			ptr += nwrite;
			ntowrite -= nwrite;
		}
	}

	clr_fl(STDOUT_FILENO, O_NONBLOCK);	/* clear nonblocking */
	exit(0);
}