STRCAT(3) BSD Library Functions Manual STRCAT(3)
NAME
strcat, strncat -- concatenate strings
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <string.h>
char *
strcat(char * restrict s, const char * restrict append);
char *
strncat(char * restrict s, const char * restrict append, size_t count);
DESCRIPTION
The strcat() and strncat() functions append a copy of the nul-terminated string append to the end of the nul-terminated string s, then add a
terminating ' '. The string s must have sufficient space to hold the result.
The strncat() function appends not more than count characters where space for the terminating ' ' should not be included in count.
RETURN VALUES
The strcat() and strncat() functions return the pointer s.
EXAMPLES
The following appends ``abc'' to ``chararray'':
char *letters = "abcdefghi";
(void)strncat(chararray, letters, 3);
The following example shows how to use strncat() safely in conjunction with strncpy(3).
char buf[BUFSIZ];
char *input, *suffix;
(void)strncpy(buf, input, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = ' ';
(void)strncat(buf, suffix, sizeof(buf) - 1 - strlen(buf));
The above will copy as many characters from ``input'' to ``buf'' as will fit. It then appends as many characters from suffix as will fit (or
none if there is no space). For operations like this, the strlcpy(3) and strlcat(3) functions are a better choice, as shown below.
(void)strlcpy(buf, input, sizeof(buf));
(void)strlcat(buf, suffix, sizeof(buf));
SEE ALSO
bcopy(3), memccpy(3), memcpy(3), memmove(3), strcpy(3), strlcat(3), strlcpy(3)
STANDARDS
The strcat() and strncat() functions conform to ISO/IEC 9899:1999 (``ISO C99'').
BSD
August 11, 2002 BSD
