1.\" $OpenBSD: fparseln.3,v 1.11 2023/01/04 13:00:11 jsg Exp $ 2.\" $NetBSD: fparseln.3,v 1.7 1999/07/02 15:49:12 simonb Exp $ 3.\" 4.\" Copyright (c) 1997 Christos Zoulas. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.Dd $Mdocdate: January 4 2023 $ 27.Dt FPARSELN 3 28.Os 29.Sh NAME 30.Nm fparseln 31.Nd return the next logical line from a stream 32.Sh SYNOPSIS 33.In stdio.h 34.In util.h 35.Ft "char *" 36.Fo fparseln 37.Fa "FILE *stream" "size_t *len" "size_t *lineno" 38.Fa "const char delim[3]" "int flags" 39.Fc 40.Sh DESCRIPTION 41The 42.Fn fparseln 43function 44returns a pointer to the next logical line from the stream referenced by 45.Fa stream . 46This string is null terminated, contains no trailing newline, 47and is dynamically allocated on each invocation. 48It is the responsibility of the caller to free the pointer. 49.Pp 50By default, if a character is escaped, both it and the preceding escape 51character will be present in the returned string. 52Various 53.Fa flags 54alter this behaviour. 55.Pp 56The meaning of the arguments is as follows: 57.Bl -tag -width "lineno" 58.It Fa stream 59The stream to read from. 60.It Fa len 61If not 62.Dv NULL , 63the length of the string is stored in the memory location referenced by 64.Fa len . 65.It Fa lineno 66If not 67.Dv NULL , 68the value of the memory location to which 69.Fa lineno 70references is incremented by the number of lines actually read from the file. 71.It Fa delim 72Contains the escape, continuation, and comment characters. 73If a character is NUL then processing for that character is disabled. 74If 75.Dv NULL , 76all characters default to values specified below. 77The contents of 78.Fa delim 79is as follows: 80.Bl -tag -width "delim[0]" 81.It Fa delim[0] 82The escape character, which defaults to 83.Ql \e , 84is used to remove any special meaning from the next character. 85.It Fa delim[1] 86The continuation character, which defaults to 87.Ql \e , 88is used to indicate that the next line should be concatenated with the 89current one if this character is the last character on the current line 90and is not escaped. 91.It Fa delim[2] 92The comment character, which defaults to 93.Ql # , 94if not escaped indicates the beginning of a comment that extends until the 95end of the current line. 96.El 97.It Fa flags 98If non-zero, alter the operation of 99.Fn fparseln . 100The various flags, which may be OR'ed together, are: 101.Bl -tag -width "FPARSELN_UNESCCOMM" 102.It Dv FPARSELN_UNESCCOMM 103Remove escape preceding an escaped comment. 104.It Dv FPARSELN_UNESCCONT 105Remove escape preceding an escaped continuation. 106.It Dv FPARSELN_UNESCESC 107Remove escape preceding an escaped escape. 108.It Dv FPARSELN_UNESCREST 109Remove escape preceding any other character. 110.It Dv FPARSELN_UNESCALL 111All of the above. 112.El 113.El 114.Sh RETURN VALUES 115Upon successful completion a pointer to the parsed line is returned; 116otherwise, 117.Dv NULL 118is returned. 119.Pp 120Internally, the 121.Fn fparseln 122function uses 123.Xr fgetln 3 , 124so all error conditions that apply to 125.Xr fgetln 3 126apply to 127.Fn fparseln 128as well. 129In addition 130.Fn fparseln 131may set 132.Va errno 133to 134.Er ENOMEM 135and return 136.Dv NULL 137if it runs out of memory. 138.Sh SEE ALSO 139.Xr fgetln 3 140