Guardian C Library Calls Reference Manual

Reference to Library Calls

Guardian TNS C Library Calls Reference Manual—128833 3-93

iscsymf (supplementary)

The iscsymf function tests whether its argument is valid as the first character of a

C identifier.

character

specifies the character to test.

Return Value

is nonzero if character is a character that can start a C identifier; otherwise, iscsymf

returns the value zero.

Usage Guidelines

•

The character-testing routine iscsymf is implemented as a macro, but the C compiler

provides an underlying function with the same name as the macro. Although the

macro is faster than the function, it evaluates its argument more than once.

Consequently, if you need to provide an expression with side effects as the argument

to this routine, you should undefine the macro so that the C compiler uses the

function instead. For more information about undefining macros, refer to the C/C++

Programmer’s Guide.

#include <ctypeh>

int iscsymf(int character);