#include <stdio.h>

int getchar(void);


Gets a character (an unsigned char) from stdin.

It is equivalent to getc(stdin).

Return value#

Upon successful completion, getchar() returns the next byte from stdin, the standard input stream. If the end-of-file indicator for stdin is set, or if stdin is at end-of-file, the end-of-file indicator for stdin is set and getchar() returns EOF. If a read error occurs, the error indicator for stdin is set, getchar() returns EOF, and sets errno to indicate the error.


  • [EAGAIN] - The O_NONBLOCK flag is set for the file descriptor underlying stream and the thread would be delayed in the getc() operation.

  • [EBADF] - The file descriptor underlying stream is not a valid file descriptor open for reading.

  • [EINTR] - The read operation was terminated due to the receipt of a signal, and no data was transferred.

  • [EIO] - A physical I/O error has occurred, or the process is in a background process group attempting to read from its controlling terminal, and either the calling thread is blocking SIGTTIN or the process is ignoring SIGTTIN or the process group of the process is orphaned.

  • [EOVERFLOW] - The file is a regular file and an attempt was made to read at or beyond the offset maximum associated with the corresponding stream.

  • [ENOMEM] - Insufficient storage space is available.

  • [ENXIO] - A request was made of a nonexistent device, or the request was outside the capabilities of the device.

Implementation tasks#

  • Implement error handling for the getchar() function.