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/* See LICENSE file for copyright and license details. */
#include "arg.h"
#include "util.h"
#include <fcntl.h>
#include <stdint.h>
#include <unistd.h>
static void
usage(void)
{
eprintf("usage: %s count file\n", argv0);
}
int
main(int argc, char *argv[])
{
struct stat st;
size_t count, ptr, n, ptw;
int fd;
ssize_t r;
char buf[BUFSIZ];
ARGBEGIN {
default:
usage();
} ARGEND;
if (argc != 2)
usage();
if (tozu(argv[0], 0, SIZE_MAX, &count))
eprintf("the count must be an integer in [0, %zu]\n", SIZE_MAX);
fd = open(argv[1], O_RDONLY);
if (fd < 0)
eprintf("open %s:", argv[1]);
while (count--) {
posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL);
for (ptr = 0;;) {
r = pread(fd, buf, sizeof(buf), ptr);
if (r < 0)
eprintf("pread %s:", argv[1]);
else if (r == 0)
break;
ptr += n = (size_t)r;
for (ptw = 0; ptw < n;) {
r = write(STDOUT_FILENO, buf + ptw, n - ptw);
if (r < 0)
eprintf("write <stdout>:");
ptw += (size_t)r;
}
}
}
close(fd);
return 0;
}
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