std::strncat

Header: <cstring>

Appends a byte string pointed to by src to a byte string pointed to by dest. At most count characters are copied. The resulting byte string is null-terminated.

# Declarations

char* strncat( char* dest, const char* src, std::size_t count );

# Parameters

• dest: pointer to the null-terminated byte string to append to
• src: pointer to the null-terminated byte string to copy from
• count: maximum number of characters to copy

# Return value

dest

# Notes

Because std::strncat needs to seek to the end of dest on each call, it is inefficient to concatenate many strings into one using std::strncat.

# Example

#include <cstdio>
#include <cstring>
 
int main() 
{
    char str[50] = "Hello ";
    const char str2[50] = "World!";
    std::strcat(str, str2);
    std::strncat(str, " Goodbye World!", 3); // may issue "truncated output" warning
    std::puts(str);
}

# See also

• strcat
• strcpy
• C documentation