#include #include #include #include #include int main() { struct stat s; int f = open("/test", O_RDWR, 0777); printf("posix_fadvise: %d\n", posix_fadvise(f, 3, 2, POSIX_FADV_DONTNEED)); printf("errno: %d\n", errno); printf("\n"); errno = 0; printf("posix_fallocate: %d\n", posix_fallocate(f, 3, 2)); printf("errno: %d\n", errno); stat("/test", &s); printf("st_size: %d\n", s.st_size); memset(&s, 0, sizeof s); printf("\n"); errno = 0; printf("posix_fallocate2: %d\n", posix_fallocate(f, 3, 7)); printf("errno: %d\n", errno); stat("/test", &s); printf("st_size: %d\n", s.st_size); memset(&s, 0, sizeof s); return 0; }