stdin(3) Library Functions Manual stdin(3) stdin stdout stderr - / (libc -lc) #include extern FILE *stdin; extern FILE *stdout; extern FILE *stderr; UNIX : . ( tty(4)) . ( " " sh(1).) " " " " " ". stdin stdout stderr. stdio(3) FILE fprintf(3) fread(3). FILEs UNIX UNIX read(2) lseek(2). stdin stdout stderr 0 1 2 . STDIN_FILENO STDOUT_FILENO STDERR_FILENO . ( freopen(3) .) FILEs . ( : POSIX.1 8.2.3 .) stdio . exec(3) . stdin stdout stderr . freopen(3) stdin stdout stderr . exit(3) . C11, POSIX.1-2008. . C89, POSIX.1-2001. stderr . stdout . fflush(3) exit(3) . . ( ) setbuf(3) setvbuf(3). stdin stdio . ( .) tcsetattr(3) stty(1) termios(3). csh(1), sh(1), open(2), fopen(3), stdio(3) 3 . . : . 6.18 21 2025 stdin(3)