Updated: April 19, 2023 |
Test a character to see if it's alphabetic
#include <ctype.h> int isalpha( int c );
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
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.
Nonzero if c is an alphabetic character; otherwise, zero.
#include <stdio.h> #include <stdlib.h> #include <ctype.h> int main( void ) { if( isalpha( (unsigned)getchar() ) ) { printf( "That's alphabetic\n" ); } return EXIT_SUCCESS; }
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |