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.\" @(#)fgets.3 6.9 (Berkeley) 6/29/91 37.\" 38.Dd June 29, 1991 39.Dt FGETS 3 40.Os 41.Sh NAME 42.Nm fgets , 43.Nm gets 44.Nd get a line from a stream 45.Sh SYNOPSIS 46.Fd #include <stdio.h> 47.Ft char * 48.Fn fgets "char *str" "size_t size" "FILE *stream" 49.Ft char * 50.Fn gets "char *str" 51.Sh DESCRIPTION 52The 53.Fn fgets 54function 55reads at most one less than the number of characters specified by 56.Xr size 57from the given 58.Fa stream 59and stores them in the string 60.Fa str . 61Reading stops when a newline character is found, 62at end-of-file or error. 63The newline, if any, is retained. 64In any case a 65.Ql \e0 66character is appended to end the string. 67.Pp 68The 69.Fn gets 70function 71is equivalent to 72.Fn fgets 73with an infinite 74.Xr size 75and a 76.Fa stream 77of 78.Em stdin , 79except that the newline character (if any) is not stored in the string. 80It is the caller's responsibility to ensure that the input line, 81if any, is sufficiently short to fit in the string. 82.Sh RETURN VALUES 83.Pp 84Upon successful completion, 85.Fn fgets 86and 87.Fn gets 88return 89a pointer to the string. 90If end-of-file or an error occurs before any characters are read, 91they return 92.Dv NULL. 93The 94.Fn fgets 95and 96functions 97.Fn gets 98do not distinguish between end-of-file and error, and callers must use 99.Xr feof 3 100and 101.Xr ferror 3 102to determine which occurred. 103.Sh ERRORS 104.Bl -tag -width [EBADF] 105.It Bq Er EBADF 106The given 107.Fa stream 108is not a readable stream. 109.El 110.Pp 111The function 112.Fn fgets 113may also fail and set 114.Va errno 115for any of the errors specified for the routines 116.Xr fflush 3 , 117.Xr fstat 2 , 118.Xr read 2 , 119or 120.Xr malloc 3 . 121.Pp 122The function 123.Fn gets 124may also fail and set 125.Va errno 126for any of the errors specified for the routine 127.Xr getchar 3 . 128.Sh SEE ALSO 129.Xr feof 3 , 130.Xr ferror 3 , 131.Xr fgetline 3 132.Sh STANDARDS 133The functions 134.Fn fgets 135and 136.Fn gets 137conform to 138.St -ansiC . 139.Sh BUGS 140Since it is usually impossible to ensure that the next input line 141is less than some arbitrary length, and because overflowing the 142input buffer is almost invariably a security violation, programs 143should 144.Em NEVER 145use 146.Fn gets . 147The 148.Fn gets 149function 150exists purely to conform to 151.St -ansiC . 152