Format
#include <ctype.h> int isascii(int c);
Language Level: XPG4, Extension
isascii tests if an integer is within the ASCII range. This macro
assumes that the system uses the ASCII character set.
Note: In earlier releases of the C/C++ run-time library, isascii began with an underscore (_isascii). Because it is defined by the X/Open standard, the underscore has been removed. For compatibility, IBM C and C++ Compilers will map _isascii to isascii for you.
Return Value
isascii returns a nonzero value if the integer is within
the ASCII set, and 0 if it is not.
Example
This example tests the integers from 0x7c to 0x82, and
prints the corresponding ASCII character if the integer is within
the ASCII range.
#include <stdio.h> #include <ctype.h>
int main(void)
{
int ch;
for (ch = 0x7c; ch <= 0x82; ch++) {
printf("%#04x ", ch);
if (isascii(ch))
printf("The ASCII character is %c\n", ch);
else
printf("Not an ASCII character\n");
}
return 0;
/************************************************
The output should be:
0x7c The ASCII character is |
0x7d The ASCII character is }
0x7e The ASCII character is ~
0x7f The ASCII character is &127
0x80 Not an ASCII character
0x81 Not an ASCII character
0x82 Not an ASCII character
************************************************/
}
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isalnum to isxdigit -- Test Integer Value
_iscsym - _iscsymf -- Test Integer
iswalnum to iswxdigit -- Test Wide
Integer Value
_toascii - _tolower - _toupper --
Convert Character
tolower - toupper -- Convert Character
Case
<ctype.h>