ISPRINT(3) BSD Programmer's Manual ISPRINT(3)
isprint - printing character test (space character inclusive)
#include <ctype.h> int isprint(int c);
The isprint() function tests for any printing character including space (' ').
The isprint() macro returns zero if the character tests false or non-zero if the character tests true.
isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3), isdigit(3), isgraph(3), islower(3), ispunct(3), isspace(3), isupper(3), isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)
The isprint() function conforms to ANSI X3.159-1989 ("ANSI C89").
The argument to isprint() must be EOF or representable as an unsigned char; otherwise, the result is undefined. MirBSD #10-current June 29, 1991 1