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/* $OpenBSD: preadv.c,v 1.2 2003/07/31 21:48:09 deraadt Exp $ */
/*
* Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
*/
#include <sys/types.h>
#include <sys/uio.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <err.h>
#include <fcntl.h>
int
main(int argc, char *argv[])
{
char temp[] = "/tmp/dup2XXXXXXXXX";
const char magic[10] = "0123456789";
char c, c1, c2;
int fd;
struct iovec iv[2];
if ((fd = mkstemp(temp)) < 0)
err(1, "mkstemp");
remove(temp);
if (write(fd, magic, sizeof(magic)) != sizeof(magic))
err(1, "write");
if (lseek(fd, 0, SEEK_SET) != 0)
err(1, "lseek");
if (read(fd, &c, 1) != 1)
err(1, "read1");
if (c != magic[0])
errx(1, "read1 %c != %c", c, magic[0]);
iv[0].iov_base = &c1;
iv[0].iov_len = 1;
iv[1].iov_base = &c2;
iv[1].iov_len = 1;
if (preadv(fd, iv, 2, 7) != 2)
err(1, "pread");
if (c1 != magic[7])
errx(1, "pread %c != %c", c1, magic[7]);
if (c2 != magic[8])
errx(1, "pread %c != %c", c2, magic[7]);
if (read(fd, &c, 1) != 1)
err(1, "read2");
if (c != magic[1])
errx(1, "read2 %c != %c", c, magic[1]);
return 0;
}
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