1.\" Copyright (c) 1990, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek and the American National Standards Committee X3, 6.\" on Information Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" from: @(#)fgets.3 6.9 (Berkeley) 6/29/91 37.\" $Id: fgets.3,v 1.4 1994/04/03 01:38:27 cgd Exp $ 38.\" 39.Dd June 29, 1991 40.Dt FGETS 3 41.Os 42.Sh NAME 43.Nm fgets , 44.Nm gets 45.Nd get a line from a stream 46.Sh SYNOPSIS 47.Fd #include <stdio.h> 48.Ft char * 49.Fn fgets "char *str" "size_t size" "FILE *stream" 50.Ft char * 51.Fn gets "char *str" 52.Sh DESCRIPTION 53The 54.Fn fgets 55function 56reads at most one less than the number of characters specified by 57.Xr size 58from the given 59.Fa stream 60and stores them in the string 61.Fa str . 62Reading stops when a newline character is found, 63at end-of-file or error. 64The newline, if any, is retained. 65In any case a 66.Ql \e0 67character is appended to end the string. 68.Pp 69The 70.Fn gets 71function 72is equivalent to 73.Fn fgets 74with an infinite 75.Xr size 76and a 77.Fa stream 78of 79.Em stdin , 80except that the newline character (if any) is not stored in the string. 81It is the caller's responsibility to ensure that the input line, 82if any, is sufficiently short to fit in the string. 83.Sh RETURN VALUES 84.Pp 85Upon successful completion, 86.Fn fgets 87and 88.Fn gets 89return 90a pointer to the string. 91If end-of-file or an error occurs before any characters are read, 92they return 93.Dv NULL. 94The 95.Fn fgets 96and 97functions 98.Fn gets 99do not distinguish between end-of-file and error, and callers must use 100.Xr feof 3 101and 102.Xr ferror 3 103to determine which occurred. 104.Sh ERRORS 105.Bl -tag -width Er 106.It Bq Er EBADF 107The given 108.Fa stream 109is not a readable stream. 110.El 111.Pp 112The function 113.Fn fgets 114may also fail and set 115.Va errno 116for any of the errors specified for the routines 117.Xr fflush 3 , 118.Xr fstat 2 , 119.Xr read 2 , 120or 121.Xr malloc 3 . 122.Pp 123The function 124.Fn gets 125may also fail and set 126.Va errno 127for any of the errors specified for the routine 128.Xr getchar 3 . 129.Sh SEE ALSO 130.Xr feof 3 , 131.Xr ferror 3 , 132.Xr fgetln 3 133.Sh STANDARDS 134The functions 135.Fn fgets 136and 137.Fn gets 138conform to 139.St -ansiC . 140.Sh BUGS 141Since it is usually impossible to ensure that the next input line 142is less than some arbitrary length, and because overflowing the 143input buffer is almost invariably a security violation, programs 144should 145.Em NEVER 146use 147.Fn gets . 148The 149.Fn gets 150function 151exists purely to conform to 152.St -ansiC . 153