git.saurik.com Git - apple/libc.git/blame_incremental

... / ...

Commit	Line	Data
	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: src/lib/libc/stdio/fgetln.3,v 1.8 2004/07/16 06:07:12 tjr Exp $
	34	.\"
	35	.Dd April 19, 1994
	36	.Dt FGETLN 3
	37	.Os
	38	.Sh NAME
	39	.Nm fgetln
	40	.Nd get a line from a stream
	41	.Sh LIBRARY
	42	.Lb libc
	43	.Sh SYNOPSIS
	44	.In stdio.h
	45	.Ft char *
	46	.Fn fgetln "FILE stream" "size_t len"
	47	.Sh DESCRIPTION
	48	The
	49	.Fn fgetln
	50	function
	51	returns a pointer to the next line from the stream referenced by
	52	.Fa stream .
	53	This line is
	54	.Em not
	55	a C string as it does not end with a terminating
	56	.Dv NUL
	57	character.
	58	The length of the line, including the final newline,
	59	is stored in the memory location to which
	60	.Fa len
	61	points.
	62	(Note, however, that if the line is the last
	63	in a file that does not end in a newline,
	64	the returned text will not contain a newline.)
	65	.Sh RETURN VALUES
	66	Upon successful completion a pointer is returned;
	67	this pointer becomes invalid after the next
	68	.Tn I/O
	69	operation on
	70	.Fa stream
	71	(whether successful or not)
	72	or as soon as the stream is closed.
	73	Otherwise,
	74	.Dv NULL
	75	is returned.
	76	The
	77	.Fn fgetln
	78	function
	79	does not distinguish between end-of-file and error; the routines
	80	.Xr feof 3
	81	and
	82	.Xr ferror 3
	83	must be used
	84	to determine which occurred.
	85	If an error occurs, the global variable
	86	.Va errno
	87	is set to indicate the error.
	88	The end-of-file condition is remembered, even on a terminal, and all
	89	subsequent attempts to read will return
	90	.Dv NULL
	91	until the condition is
	92	cleared with
	93	.Xr clearerr 3 .
	94	.Pp
	95	The text to which the returned pointer points may be modified,
	96	provided that no changes are made beyond the returned size.
	97	These changes are lost as soon as the pointer becomes invalid.
	98	.Sh ERRORS
	99	.Bl -tag -width Er
	100	.It Bq Er EBADF
	101	The argument
	102	.Fa stream
	103	is not a stream open for reading.
	104	.El
	105	.Pp
	106	The
	107	.Fn fgetln
	108	function
	109	may also fail and set
	110	.Va errno
	111	for any of the errors specified for the routines
	112	.Xr fflush 3 ,
	113	.Xr malloc 3 ,
	114	.Xr read 2 ,
	115	.Xr stat 2 ,
	116	or
	117	.Xr realloc 3 .
	118	.Sh SEE ALSO
	119	.Xr ferror 3 ,
	120	.Xr fgets 3 ,
	121	.Xr fgetwln 3 ,
	122	.Xr fopen 3 ,
	123	.Xr putc 3
	124	.Sh HISTORY
	125	The
	126	.Fn fgetln
	127	function first appeared in
	128	.Bx 4.4 .