STRCAT(3) Linux Programmer's Manual STRCAT(3)NAME
strcat, strncat - concatenate two strings
SYNOPSIS
#include <string.h>
char *strcat(char *dest, const char *src);
char *strncat(char *dest, const char *src, size_t n);
DESCRIPTION
The strcat() function appends the src string to the dest string, over‐
writing the terminating null byte ('\0') at the end of dest, and then
adds a terminating null byte. The strings may not overlap, and the
dest string must have enough space for the result.
The strncat() function is similar, except that
* it will use at most n characters from src; and
* src does not need to be null-terminated if it contains n or more
characters.
As with strcat(), the resulting string in dest is always null-termi‐
nated.
If src contains n or more characters, strncat() writes n+1 characters
to dest (n from src plus the terminating null byte). Therefore, the
size of dest must be at least strlen(dest)+n+1.
A simple implementation of strncat() might be:
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] != '\0' ; i++)
dest[dest_len + i] = src[i];
dest[dest_len + i] = '\0';
return dest;
}
RETURN VALUE
The strcat() and strncat() functions return a pointer to the resulting
string dest.
CONFORMING TO
SVr4, 4.3BSD, C89, C99.
SEE ALSObcopy(3), memccpy(3), memcpy(3), strcpy(3), string(3), strncpy(3),
wcscat(3), wcsncat(3)COLOPHON
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be found at http://man7.org/linux/man-pages/.
GNU 2011-09-28 STRCAT(3)