+++ /dev/null
-.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" References consulted:
-.\" Linux libc source code
-.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
-.\" 386BSD man pages
-.\" Modified Sat Jul 24 18:11:47 1993 by Rik Faith (faith@cs.unc.edu)
-.\" 2007-06-15, Marc Boyer <marc.boyer@enseeiht.fr> + mtk
-.\" Improve discussion of strncat().
-.TH STRCAT 3 2014-01-20 "GNU" "Linux Programmer's Manual"
-.SH NAME
-strcat, strncat \- concatenate two strings
-.SH SYNOPSIS
-.nf
-.B #include <string.h>
-.sp
-.BI "char *strcat(char *" dest ", const char *" src );
-.sp
-.BI "char *strncat(char *" dest ", const char *" src ", size_t " n );
-.fi
-.SH DESCRIPTION
-The
-.BR strcat ()
-function appends the
-.I src
-string to the
-.I dest
-string,
-overwriting the terminating null byte (\(aq\\0\(aq) at the end of
-.IR dest ,
-and then adds a terminating null byte.
-The strings may not overlap, and the
-.I dest
-string must have
-enough space for the result.
-If
-.I dest
-is not large enough, program behavior is unpredictable;
-.IR "buffer overruns are a favorite avenue for attacking secure programs" .
-.PP
-The
-.BR strncat ()
-function is similar, except that
-.IP * 3
-it will use at most
-.I n
-bytes from
-.IR src ;
-and
-.IP *
-.I src
-does not need to be null-terminated if it contains
-.I n
-or more bytes.
-.PP
-As with
-.BR strcat (),
-the resulting string in
-.I dest
-is always null-terminated.
-.PP
-If
-.IR src
-contains
-.I n
-or more bytes,
-.BR strncat ()
-writes
-.I n+1
-bytes to
-.I dest
-.RI ( n
-from
-.I src
-plus the terminating null byte).
-Therefore, the size of
-.I dest
-must be at least
-.IR "strlen(dest)+n+1" .
-
-A simple implementation of
-.BR strncat ()
-might be:
-.in +4n
-.nf
-
-char*
-strncat(char *dest, const char *src, size_t n)
-{
- size_t dest_len = strlen(dest);
- size_t i;
-
- for (i = 0 ; i < n && src[i] != \(aq\\0\(aq ; i++)
- dest[dest_len + i] = src[i];
- dest[dest_len + i] = \(aq\\0\(aq;
-
- return dest;
-}
-.fi
-.in
-.SH RETURN VALUE
-The
-.BR strcat ()
-and
-.BR strncat ()
-functions return a pointer to the resulting string
-.IR dest .
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR strcat ()
-and
-.BR strncat ()
-functions are thread-safe.
-.SH CONFORMING TO
-SVr4, 4.3BSD, C89, C99.
-.SH NOTES
-Some systems (the BSDs, Solaris, and others) provide the following function:
-
- size_t strlcat(char *dest, const char *src, size_t size);
-
-This function appends the null-terminated string
-.I src
-to the string
-.IR dest ,
-copying at most
-.IR "size\-strlen(dest)\-1"
-from
-.IR src ,
-and adds a terminating null byte to the result,
-.I unless
-.IR size
-is less than
-.IR strlen(dest) .
-This function fixes the buffer overrun problem of
-.BR strcat (),
-but the caller must still handle the possibility of data loss if
-.I size
-is too small.
-The function returns the length of the string
-.BR strlcat ()
-tried to create; if the return value is greater than or equal to
-.IR size ,
-data loss occurred.
-If data loss matters, the caller
-.I must
-either check the arguments before the call, or test the function return value.
-.BR strlcat ()
-is not present in glibc and is not standardized by POSIX,
-.\" https://lwn.net/Articles/506530/
-but is available on Linux via the
-.IR libbsd
-library.
-.SH SEE ALSO
-.BR bcopy (3),
-.BR memccpy (3),
-.BR memcpy (3),
-.BR strcpy (3),
-.BR string (3),
-.BR strncpy (3),
-.BR wcscat (3),
-.BR wcsncat (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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