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.\" $OpenBSD: strcpy.3,v 1.10 2000/04/21 15:24:20 aaron Exp $ 37.\" 38.Dd June 29, 1991 39.Dt STRCPY 3 40.Os 41.Sh NAME 42.Nm strcpy , 43.Nm strncpy 44.Nd copy strings 45.Sh SYNOPSIS 46.Fd #include <string.h> 47.Ft char * 48.Fn strcpy "char *dst" "const char *src" 49.Ft char * 50.Fn strncpy "char *dst" "const char *src" "size_t len" 51.Sh DESCRIPTION 52The 53.Fn strcpy 54and 55.Fn strncpy 56functions copy the string 57.Fa src 58to 59.Fa dst 60(including the terminating 61.Ql \e0 62character). 63.Pp 64.Fn strncpy 65copies not more than 66.Fa len 67characters into 68.Fa dst , 69appending 70.Ql \e0 71characters if 72.Fa src 73is less than 74.Fa len 75characters long, and 76.Em not 77terminating 78.Fa dst 79if 80.Fa src 81is more than 82.Fa len 83characters long. 84.Sh RETURN VALUES 85The 86.Fn strcpy 87and 88.Fn strncpy 89functions return 90.Fa dst . 91.Sh EXAMPLES 92The following sets 93.Va chararray 94to 95.Dq abc\e0\e0\e0 : 96.Bd -literal -offset indent 97(void)strncpy(chararray, "abc", 6); 98.Ed 99.Pp 100The following sets 101.Va chararray 102to 103.Dq abcdef 104and does 105.Em not 106null terminate 107.Va chararray 108because the source string is >= the length parameter. 109.Fn strncpy 110.Em only 111null terminates the destination string when then length of the source 112string is less than the length parameter. 113.Bd -literal -offset indent 114(void)strncpy(chararray, "abcdefgh", 6); 115.Ed 116.Pp 117The following copies as many characters from 118.Va input 119to 120.Va buf 121as will fit and null terminates the result. 122Because 123.Fn strncpy 124does 125.Em not 126guarantee to null terminate the string itself, we must do this by hand. 127.Bd -literal -offset indent 128char buf[BUFSIZ]; 129 130(void)strncpy(buf, input, sizeof(buf) - 1); 131buf[sizeof(buf) - 1] = '\e0'; 132.Ed 133.Pp 134Note that 135.Xr strlcpy 3 136is a better choice for this kind of operation. 137The equivalent using 138.Xr strlcpy 3 139is simply: 140.Bd -literal -offset indent 141(void)strlcpy(buf, input, sizeof(buf)); 142.Ed 143.Sh SEE ALSO 144.Xr bcopy 3 , 145.Xr memccpy 3 , 146.Xr memcpy 3 , 147.Xr memmove 3 , 148.Xr strlcpy 3 149.Sh STANDARDS 150The 151.Fn strcpy 152and 153.Fn strncpy 154functions conform to 155.St -ansiC . 156