Converts all lower case ASCII letters to upper case ASCII letters.
a string
length of @str in bytes, or -1 if @str is nul-terminated
a newly allocated string, with all the lower case characters in @str converted to upper case, with semantics that exactly match g_ascii_toupper(). (Note that this is unlike the old g_strup(), which modified the string in place.)
See Implementation
Converts all lower case ASCII letters to upper case ASCII letters.