c++ - copying from a std::string to a char array and null-terminating the result -

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i have visual studio 2008 c++03 application want copy std::string char array, need char array null terminated if must truncate string so.

this, instance works desired:

inline void copyandnullterminate( const std::string& source,                                    char* dest,                                    size_t dest_size ) {     source.copy( dest, dest_size );     using std::min;     char* end = dest + min( dest_size - 1, source.size() );     *end = '\0'; }  int main() {     enum{ max_string_size = 15 };     char dest[ max_string_size ];     std::string test = "this test";      copyandnullterminate( test, dest, max_string_size );      assert( strcmp( test.c_str(), dest ) == 0 );     return 0; }

example: http://ideone.com/0ebyb

is there shorter, more efficient method of doing this?

thanks

yes, use strncpy, defined in cstring: 

void copystring(const std::string& input, char *dst, size_t dst_size) {     strncpy(dst, input.c_str(), dst_size - 1);     dst[dst_size - 1] = '\0'; }

note implementations of std::string (as pointed out @k-ballo), may shorter, less efficient. due fact std::string not guaranteed implemented using c-syle strings, although situations case.


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