1 /* $OpenBSD: pwritev.c,v 1.5 2011/11/06 15:00:34 guenther Exp $ */ 2 /* 3 * Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain. 4 */ 5 #include <sys/types.h> 6 #include <sys/uio.h> 7 #include <err.h> 8 #include <errno.h> 9 #include <fcntl.h> 10 #include <limits.h> 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <string.h> 14 #include <unistd.h> 15 16 int 17 main(int argc, char *argv[]) 18 { 19 char temp[] = "/tmp/pwritevXXXXXXXXX"; 20 char magic[10] = "0123456789"; 21 const char zeroes[10] = "0000000000"; 22 char buf[10]; 23 struct iovec iov[2]; 24 char c; 25 int fd, ret; 26 27 if ((fd = mkstemp(temp)) < 0) 28 err(1, "mkstemp"); 29 remove(temp); 30 31 if (write(fd, zeroes, sizeof(zeroes)) != sizeof(zeroes)) 32 err(1, "write"); 33 34 if (lseek(fd, 5, SEEK_SET) != 5) 35 err(1, "lseek"); 36 37 iov[0].iov_base = &magic[8]; 38 iov[0].iov_len = 2; 39 iov[1].iov_base = &magic[7]; 40 iov[1].iov_len = 2; 41 42 if (pwritev(fd, iov, 2, 4) != 4) 43 err(1, "pwritev"); 44 45 if (read(fd, &c, 1) != 1) 46 err(1, "read"); 47 48 if (c != '9') 49 errx(1, "read %c != %c", c, '9'); 50 51 c = '5'; 52 if (write(fd, &c, 1) != 1) 53 err(1, "write"); 54 55 if (pread(fd, buf, 10, 0) != 10) 56 err(1, "pread"); 57 58 iov[1].iov_base = &magic[1]; 59 iov[1].iov_len = 2; 60 if ((ret = pwritev(fd, iov, 2, -1)) != -1) 61 errx(1, "pwritev with negative offset succeeded,\ 62 returning %d", ret); 63 if (errno != EINVAL) 64 err(1, "pwritev with negative offset"); 65 66 if ((ret = pwritev(fd, iov, 2, LLONG_MAX)) != -1) 67 errx(1, "pwritev with wrapping offset succeeded,\ 68 returning %d", ret); 69 if (errno != EFBIG && errno != EINVAL) 70 err(1, "pwritev with wrapping offset"); 71 72 if (memcmp(buf, "0000895800", 10) != 0) 73 errx(1, "data mismatch: %s != %s", buf, "0000895800"); 74 75 /* pwrite should be unaffected by O_APPEND */ 76 if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_APPEND)) 77 err(1, "fcntl"); 78 if (pwritev(fd, iov, 2, 2) != 4) 79 err(1, "pwritev"); 80 if (pread(fd, buf, 10, 0) != 10) 81 err(1, "pread"); 82 if (memcmp(buf, "0089125800", 10) != 0) 83 errx(1, "data mismatch: %s != %s", buf, "0089125800"); 84 85 close(fd); 86 87 /* also, verify that pwritev fails on ttys */ 88 fd = open("/dev/tty", O_RDWR); 89 if (fd < 0) 90 printf("skipping tty test\n"); 91 else if ((ret = pwritev(fd, iov, 2, 7)) != -1) 92 errx(1, "pwritev succeeded on tty, returning %d", ret); 93 else if (errno != ESPIPE) 94 err(1, "pwritev"); 95 96 return 0; 97 } 98