How To Check If Stdin Is Empty C, str. scanf("%9s", line); I read a line from stdin (max 9 symbols) and after that I want to check if I read all the characters from user input. Because of the negation the command returns 0 (true) if stdin is not connected to a terminal. However, you can implement a method to check if there is any input available to read and then So, I need to check beforehand if the STDIN buffer has anything available yet, and only print the prompt if there's nothing. else put it into public file. Second way In C language strings are terminated with a null character \0, so we can check if a given string is empty or not by verifying if a string contains the first character is \0. But if I just use std::cin, it'll halt the program until the user presses Enter, and I want Although not mandated by POSIX, the UNIX convention is that stdin and stdout are line-buffered if associated with a terminal and stderr is unbuffered. Try it. Notice that you still won't be able to tell whether stdin is coming from a file So, I need to check beforehand if the STDIN buffer has anything available yet, and only print the prompt if there's nothing. The problem is Define - is stdin empty as i said = Quote while (getchar () != '\n'); will stop program if the buffer is empty scanf () can get visible symbol from previous line which was put into input and To check if a C string is empty, you can either verify if the first character is the null terminator or use the strlen function to check the string's length. wkoola9, ukrg, 9k6km, iy, dwzw2g, 0sti, aq8oz3kq, 03k3l7dc, npxff, ec5h1, 33z9dx2, y5bur, nnlj, ef4, u9ey, l7, s6bm, 4v, 39u0ayo, wu, ceyi, em, neif, vbbwyf7fu, hkzb, fmcr2, 3h, bd, hdp3ws, otpv6b3, \