1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)fgetln.3 8.3 (Berkeley) 4/19/94 29.\" $FreeBSD: head/lib/libc/stdio/fgetwln.3 165903 2007-01-09 00:28:16Z imp $ 30.\" 31.Dd July 16, 2004 32.Dt FGETWLN 3 33.Os 34.Sh NAME 35.Nm fgetwln 36.Nd get a line of wide characters from a stream 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In stdio.h 41.In wchar.h 42.Ft wchar_t * 43.Fn fgetwln "FILE * restrict stream" "size_t * restrict len" 44.Sh DESCRIPTION 45The 46.Fn fgetwln 47function 48returns a pointer to the next line from the stream referenced by 49.Fa stream . 50This line is 51.Em not 52a standard wide character string as it does not end with a terminating 53null wide character. 54The length of the line, including the final newline, 55is stored in the memory location to which 56.Fa len 57points. 58(Note, however, that if the line is the last 59in a file that does not end in a newline, 60the returned text will not contain a newline.) 61.Sh RETURN VALUES 62Upon successful completion a pointer is returned; 63this pointer becomes invalid after the next 64.Tn I/O 65operation on 66.Fa stream 67(whether successful or not) 68or as soon as the stream is closed. 69Otherwise, 70.Dv NULL 71is returned. 72The 73.Fn fgetwln 74function 75does not distinguish between end-of-file and error; the routines 76.Xr feof 3 77and 78.Xr ferror 3 79must be used 80to determine which occurred. 81If an error occurs, the global variable 82.Va errno 83is set to indicate the error. 84The end-of-file condition is remembered, even on a terminal, and all 85subsequent attempts to read will return 86.Dv NULL 87until the condition is 88cleared with 89.Xr clearerr 3 . 90.Pp 91The text to which the returned pointer points may be modified, 92provided that no changes are made beyond the returned size. 93These changes are lost as soon as the pointer becomes invalid. 94.Sh ERRORS 95.Bl -tag -width Er 96.It Bq Er EBADF 97The argument 98.Fa stream 99is not a stream open for reading. 100.El 101.Pp 102The 103.Fn fgetwln 104function 105may also fail and set 106.Va errno 107for any of the errors specified for the routines 108.Xr mbrtowc 3 , 109.Xr realloc 3 , 110or 111.Xr read 2 . 112.Sh SEE ALSO 113.Xr ferror 3 , 114.Xr fgetln 3 , 115.Xr fgetws 3 , 116.Xr fopen 3 117