1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. 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 8.1 (Berkeley) 6/4/93 37.\" 38.Dd June 4, 1993 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" "int 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.Fa 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. 64If any characters are read and there is no error, 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.Fa 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 occurs before any characters are read, 91they return 92.Dv NULL 93and the buffer contents is unchanged. 94If an error occurs, 95they return 96.Dv NULL 97and the buffer contents is indeterminate. 98The 99.Fn fgets 100and 101.Fn gets 102functions 103do not distinguish between end-of-file and error, and callers must use 104.Xr feof 3 105and 106.Xr ferror 3 107to determine which occurred. 108.Sh ERRORS 109.Bl -tag -width [EBADF] 110.It Bq Er EBADF 111The given 112.Fa stream 113is not a readable stream. 114.El 115.Pp 116The function 117.Fn fgets 118may also fail and set 119.Va errno 120for any of the errors specified for the routines 121.Xr fflush 3 , 122.Xr fstat 2 , 123.Xr read 2 , 124or 125.Xr malloc 3 . 126.Pp 127The function 128.Fn gets 129may also fail and set 130.Va errno 131for any of the errors specified for the routine 132.Xr getchar 3 . 133.Sh SEE ALSO 134.Xr feof 3 , 135.Xr ferror 3 , 136.Xr fgetln 3 137.Sh STANDARDS 138The functions 139.Fn fgets 140and 141.Fn gets 142conform to 143.St -ansiC . 144.Sh BUGS 145Since it is usually impossible to ensure that the next input line 146is less than some arbitrary length, and because overflowing the 147input buffer is almost invariably a security violation, programs 148should 149.Em NEVER 150use 151.Fn gets . 152The 153.Fn gets 154function 155exists purely to conform to 156.St -ansiC . 157