linux - loop through a file and print file attributes in C -
i new programming in c. need program loop through files in folder , print these attributes each file. @ point printing attributes of folder.
#include <sys/types.h> #include <sys/stat.h> #include <stdlib.h> #include <stdio.h> #include <time.h> #include <dirent.h> int main(int argc, char *argv[]) { dir *dp; struct stat file_stats; if (argc != 2) { fprintf(stderr, "usage: fstat file...\n"); return exit_failure; } if ((stat(argv[1], &file_stats)) == -1) { perror("fstat"); return exit_failure; } dp = opendir("./"); if (dp == null) { perror("couldn't open directory"); return exit_failure; } while (readdir(dp)) { printf("filename: %s\n", argv[1]); printf(" device: %lld\n", file_stats.st_dev); printf(" protection: %o\n", file_stats.st_mode); printf(" number of hard links: %d\n", file_stats.st_nlink); printf(" user id of owner: %d\n", file_stats.st_uid); printf(" group id of owner: %d\n", file_stats.st_gid); printf(" device type (if inode device): %lld\n", file_stats.st_rdev); printf(" total size, in bytes: %ld\n", file_stats.st_size); printf(" blocksize filesystem i/o: %ld\n", file_stats.st_blksize); printf(" inode number: %lu\n", file_stats.st_ino); printf(" time of last access: %ld : %s", file_stats.st_atime, ctime(&file_stats.st_atime)); printf(" time of last change: %ld : %s", file_stats.st_ctime, ctime(&file_stats.st_ctime)); closedir(dp); } return exit_success; } i think need move struct while loop when compiler says "file_stats undeclared."
in addition valentin's answer, should move closedir() out of loop.
update: need replace stat(argv[1], ...) stat(ep->d_name, ...) obtain information actual file. before need enter argv[1] directory (using chdir() system call).
completely working code:
#include <sys/types.h> #include <sys/stat.h> #include <stdlib.h> #include <stdio.h> #include <time.h> #include <dirent.h> #include <unistd.h> int main(int argc, char *argv[]) { dir *dp; struct stat file_stats; struct dirent *ep; int ret = exit_success; int ret2; if (argc != 2) { fprintf(stderr, "usage: %s file...\n", argv[0]); return exit_failure; } dp = opendir(argv[1]); if (dp == null) { perror("couldn't open directory"); return exit_failure; } ret2 = chdir(argv[1]); if (ret2 == -1) { perror("unable change directory"); ret = exit_failure; goto out1; } while ((ep = readdir(dp))) { printf("filename: %s\n", ep->d_name); if ((stat(ep->d_name, &file_stats)) == -1) { perror("fstat"); ret = exit_failure; goto out2; } printf(" device: %lld\n", file_stats.st_dev); printf(" protection: %o\n", file_stats.st_mode); printf(" number of hard links: %d\n", file_stats.st_nlink); printf(" user id of owner: %d\n", file_stats.st_uid); printf(" group id of owner: %d\n", file_stats.st_gid); printf(" device type (if inode device): %lld\n", file_stats.st_rdev); printf(" total size, in bytes: %ld\n", file_stats.st_size); printf(" blocksize filesystem i/o: %ld\n", file_stats.st_blksize); printf(" inode number: %lu\n", file_stats.st_ino); printf(" time of last access: %ld : %s", file_stats.st_atime, ctime(&file_stats.st_atime)); printf(" time of last change: %ld : %s\n", file_stats.st_ctime, ctime(&file_stats.st_ctime)); } out2: ret2 = chdir(".."); if (ret2 == -1) { perror("unable change directory back"); ret = exit_failure; goto out1; } out1: closedir(dp); return ret; }