C language strupr() function: Convert all lowercase letters in a string to uppercase

Function name : strupr

Header file : <string.h>

Function prototype: char *strupr(char *str);

Function : Convert all lowercase letters in the string to uppercase

Parameters : char *str is the string to be converted

Return value : Returns the converted uppercase string

Note : This function does not generate a new string, but modifies the original string. Therefore, str can only be a character array, not the string pointed to by the string pointer, because the string pointer points to a string constant, and the constant cannot be modified.

Program example: Convert all lowercase letters in the string array str to uppercase

 #include<string.h>#include<stdio.h>intmain(void){charstr[20]=wWw.dotCpp.coM,*ptr;ptr=strupr(str);printf(%sn,ptr); return0;}

Running results:

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