test to see if a character is a letter
#include <ctype.h> int isalpha( int c );
The isalpha() function tests if the argument c is an alphabetic character ('a' to 'z' and 'A' to 'Z'). An alphabetic character is any character for which isupper() or islower() is true.
Zero if the argument isn't an alphabetic character; otherwise, a nonzero value.
#include <stdio.h> #include <ctype.h> void main() { if( isalpha( getchar() ) ) { printf( "is alphabetic\n" ); } }
ANSI
Safety: | |
---|---|
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |
isalnum(), iscntrl(), isdigit(), isgraph(), islower(), isprint(), ispunct(), isspace(), isupper(), isxdigit()