Updated: April 19, 2023 |
Test a character to see if it's a 7-bit ASCII character
#include <ctype.h> int isascii( int c );
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The isascii() function tests for an ASCII character (in the range 0 to 127).
Nonzero if c is an ASCII character; otherwise, zero.
#include <stdio.h> #include <stdlib.h> #include <ctype.h> char the_chars[] = { 'A', 0x80, 'Z' }; #define SIZE sizeof( the_chars ) / sizeof( char ) int main( void ) { int i; for( i = 0; i < SIZE; i++ ) { if( isascii( (unsigned)the_chars[i] ) ) { printf( "Char %c is an ASCII character\n", the_chars[i] ); } else { printf( "Char %c is not an ASCII character\n", the_chars[i] ); } } return EXIT_SUCCESS; }
produces the output:
Char A is an ASCII character Char is not an ASCII character Char Z is an ASCII character
POSIX 1003.1 OB XSI. This function is marked as obsolescent, and may be removed from a future version of the standard.
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |