Implementation status: to be implemented


#include <stdio.h>

#include <wchar.h>

wchar_t *fgetws(wchar_t *ws, int n, FILE *stream);


The function gets a wide-character string from a stream.


ws - the array saving the read wide character string,
n - the maximum number of wide characters to read +1,
stream - the input stream.

The fgetws() function reads characters from the stream, converts these to the corresponding wide-character codes, places them in the wchar_t array pointed to by ws, until n-1 characters are read, or a is read, converted, and transferred to ws, or an end-of-file condition is encountered. The wide-character string, ws, is then terminated with a null wide-character code.

If an error occurs, the resulting value of the file position indicator for the stream is unspecified.

Return value

Upon successful completion, the fgetws() function returns ws.
If the end-of-file indicator for the stream is set, or if the stream is at end-of-file, the end-of-file indicator for the stream is set and fgetws() returns a null pointer 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 fgetwc() operation.
[EBADF] The file descriptor underlying stream is not a valid file descriptor open for reading.
[EILSEQ] The data obtained from the input stream does not form a valid character.
[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 wchar.h file.
  • Implement the fgetws() function.