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va_start()
Start getting items from a variable argument list

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va_start()

QNX SDP8.0C Library ReferenceAPIDeveloper

Start getting items from a variable argument list

Synopsis:

#include <stdarg.h>

void va_start( va_list param, 
               previous );

Arguments:

param: A va_list object that the varargs macros can use to locate the arguments.
previous: The argument that immediately precedes the "..." notation in the original function definition.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

Use the va_start() macro to start the acquisition of arguments from a list of variable arguments.

You must use the va_start() macro with the associated macros va_arg(), va_copy(), and va_end(). For each call to va_start(), you must have a matching call to va_end(). For more information, see va_arg().

Examples:

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Caveats:

va_start() is a macro.

Page updated: August 09, 2024