/* * cat * * Concatenates files together to standard output. * In a supporting terminal, you can then pipe * standard out to another file or other useful * things like that. */ #include #include #include #define CHUNK_SIZE 4096 void doit(int fd) { while (1) { char buf[CHUNK_SIZE]; int r = read(fd, buf, CHUNK_SIZE); if (!r) return; fwrite(buf, 1, r, stdout); fflush(stdout); } } int main(int argc, char ** argv) { int ret = 0; if (argc == 1) { doit(0); } for (int i = 1; i < argc; ++i) { int fd = open(argv[i], O_RDONLY); if (fd == -1) { fprintf(stderr, "%s: %s: no such file or directory\n", argv[0], argv[i]); ret = 1; continue; } struct stat _stat; fstat(fd, &_stat); if (S_ISDIR(_stat.st_mode)) { fprintf(stderr, "%s: %s: Is a directory\n", argv[0], argv[i]); close(fd); ret = 1; continue; } doit(fd); close(fd); } return ret; } /* * vim:tabstop=4 * vim:noexpandtab * vim:shiftwidth=4 */