NAME
fgetwln —
get a line of wide characters from a
stream
SYNOPSIS
#include <stdio.h>
#include <wchar.h>
wchar_t *
fgetwln(FILE
* restrict stream, size_t
* restrict len);
DESCRIPTION
The
fgetwln()
function returns a pointer to the next line from the stream referenced by
stream. This line is
not a
standard wide-character string as it does not end with a terminating null
wide character. The length of the line, including the final newline, is
stored in the memory location to which len points and
is guaranteed to be greater than 0 upon successful completion. (Note,
however, that if the last line in the stream does not end in a newline, the
returned text will not contain a newline.)
RETURN VALUES
Upon successful completion a pointer is returned; this pointer
becomes invalid after the next I/O operation on stream
(whether successful or not) or as soon as the stream is closed. Otherwise,
NULL is returned.
The fgetwln() function does not
distinguish between end-of-file and error; the routines
feof(3) and
ferror(3)
must be used to determine which occurred. If an error occurs, the global
variable errno is set to indicate the error. The
end-of-file condition is remembered, even on a terminal, and all subsequent
attempts to read will return NULL until the
condition is cleared with
clearerr(3).
The text to which the returned pointer points may be modified, provided that no changes are made beyond the returned size. These changes are lost as soon as the pointer becomes invalid.
ERRORS
- [
EBADF] - The argument stream is not a stream open for reading.
The fgetwln() function may also fail and
set errno for any of the errors specified for the
routines malloc(3), mbrtowc(3), read(2), stat(2), or
realloc(3).
SEE ALSO
HISTORY
The fgetwln() function first appeared in
OpenBSD 5.7.