字符串中提取数字

int main(int argc, char** argv)
{
   char str[] = ":SE:FR:STOP 38.2MHz";
    
   char *p = str;
   char temp[12];
   int i = 0;
 
   memset(temp, 0, sizeof(temp));
   while( *p != '\0' )
   {
      if(isdigit(*p) || (*p == '.') )
      {
         temp[i++] = *p;
      }
      p++;
   }
   float num = atof(temp);
    
}