toupper

I'm pretty new to C and am hitting a wall when creating the below function. I want to use this function to make the first letter of a word upper case for a static character array (char string[]. It looks ok to my eye, but I'm getting some syntax errors which are probably pretty basic. compiler errors: error: invalid conversion from const char' to const char*' initializing argument 1 of `size_t strlen(const char*)' assignment of read-only location void Cap(char string[]){ int i; int x = strlen(string); for (i=1;i<x;i++){ if (isalpha(string[i]) && string[i-1] == ' '){ // only first letters of a

In C, strings are arrays of char ( char * ) and characters are usually stored in char . I noticed that some functions from the libC are taking as argument integers instead of a char. For instance, let's take the functions toupper() and tolower() that both use int . The man page says: If c is not an unsigned char value, or EOF, the behavior of these functions is undefined. My guess is that with a int , toupper and tolower are able to deal with unsigned char and EOF . But in fact EOF is in practice (is there any rule about its value?) a value that can be stored with a char , and since those

Given the code: #include <iostream> #include <cctype> #include <string> #include <algorithm> using namespace std; int main() { string s("ABCDEFGHIJKL"); transform(s.begin(),s.end(),s.begin(),tolower); cout<<s<<endl; } I get the error: No matching function for call to transform(__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator