islower

isgraph

#include <ctype.h>int isgraph(int ch);

The isgraph( ) function returns nonzero if ch is any printable character other than a space; otherwise, zero is returned. For ASCII environments, printable characters are in the range 0x21 through 0x7E.

Related functions are isalnum( ), isalpha( ), iscntrl( ), isdigit( ), isprint( ), ispunct( ), and isspace( ).