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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)fgetln.3 8.3 (Berkeley) 4/19/94 33.\" $FreeBSD$ 34.\" 35.Dd July 16, 2004 36.Dt FGETWLN 3 37.Os 38.Sh NAME 39.Nm fgetwln 40.Nd get a line of wide characters from a stream 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In stdio.h 45.In wchar.h 46.Ft wchar_t * 47.Fn fgetwln "FILE * restrict stream" "size_t * restrict len" 48.Sh DESCRIPTION 49The 50.Fn fgetwln 51function 52returns a pointer to the next line from the stream referenced by 53.Fa stream . 54This line is 55.Em not 56a standard wide character string as it does not end with a terminating 57null wide character. 58The length of the line, including the final newline, 59is stored in the memory location to which 60.Fa len 61points. 62(Note, however, that if the line is the last 63in a file that does not end in a newline, 64the returned text will not contain a newline.) 65.Sh RETURN VALUES 66Upon successful completion a pointer is returned; 67this pointer becomes invalid after the next 68.Tn I/O 69operation on 70.Fa stream 71(whether successful or not) 72or as soon as the stream is closed. 73Otherwise, 74.Dv NULL 75is returned. 76The 77.Fn fgetwln 78function 79does not distinguish between end-of-file and error; the routines 80.Xr feof 3 81and 82.Xr ferror 3 83must be used 84to determine which occurred. 85If an error occurs, the global variable 86.Va errno 87is set to indicate the error. 88The end-of-file condition is remembered, even on a terminal, and all 89subsequent attempts to read will return 90.Dv NULL 91until the condition is 92cleared with 93.Xr clearerr 3 . 94.Pp 95The text to which the returned pointer points may be modified, 96provided that no changes are made beyond the returned size. 97These changes are lost as soon as the pointer becomes invalid. 98.Sh ERRORS 99.Bl -tag -width Er 100.It Bq Er EBADF 101The argument 102.Fa stream 103is not a stream open for reading. 104.El 105.Pp 106The 107.Fn fgetwln 108function 109may also fail and set 110.Va errno 111for any of the errors specified for the routines 112.Xr mbrtowc 3 , 113.Xr realloc 3 , 114or 115.Xr read 2 . 116.Sh SEE ALSO 117.Xr ferror 3 , 118.Xr fgetln 3 , 119.Xr fgetws 3 , 120.Xr fopen 3 121