Full prototype:
int isprint(int);  
Purpose and Notes:
Used to test whether or not the the argument passed into the function is a printable character according to the set locale. (including the space ' ' character)
It is the same as the
isgraph() function except that it includes the space ' ' character.
Returns:
int- C-style true or false dpending on if the character passed in to the function is printable or not. If it is, it returns a C-style true and otherwise it returns a C-style false.
Argument 1:
int- Character (including the EOF character, hence int instead of char) to be evaluated to determine if it a printable character according to the current locale.