有谁用过可变参数的函数吗?

[sstower]

BOOL mkstbblerrlgPut(unsigned int iModule, unsigned int iErrorNo, ...)

...就代表可变参数,我要实现这个函数,怎样取得它的值?

[88dd]

int iPara;
va_start(vl, iPara);
把一个参数转换成int型，装入变量iPara中

取参数循环
va_list vl;
va_end(vl);

具体可看
va_list
va_start
va_end
宏定义及帮助

[yongdu]

msdn例子

Example
/* VA.C: The program below illustrates passing a variable
* number of arguments using the following macros:
* va_start va_arg va_end
* va_list va_dcl (UNIX only)
*/

#include <stdio.h>
#define ANSI /* Comment out for UNIX version */
#ifdef ANSI /* ANSI compatible version */
#include <stdarg.h>
int average( int first, ... );
#else /* UNIX compatible version */
#include <varargs.h>
int average( va_list );
#endif

void main( void )
{
/* Call with 3 integers (-1 is used as terminator). */
printf( "Average is: %d\n", average( 2, 3, 4, -1 ) );

/* Call with 4 integers. */
printf( "Average is: %d\n", average( 5, 7, 9, 11, -1 ) );

/* Call with just -1 terminator. */
printf( "Average is: %d\n", average( -1 ) );
}

/* Returns the average of a variable list of integers. */
#ifdef ANSI /* ANSI compatible version */
int average( int first, ... )
{
int count = 0, sum = 0, i = first;
va_list marker;

va_start( marker, first ); /* Initialize variable arguments. */
while( i != -1 )
{
sum += i;
count++;
i = va_arg( marker, int);
}
va_end( marker ); /* Reset variable arguments. */
return( sum ? (sum / count) : 0 );
}
#else /* UNIX compatible version must use old-style definition. */
int average( va_alist )
va_dcl
{
int i, count, sum;
va_list marker;

va_start( marker ); /* Initialize variable arguments. */
for( sum = count = 0; (i = va_arg( marker, int)) != -1; count++ )
sum += i;
va_end( marker ); /* Reset variable arguments. */
return( sum ? (sum / count) : 0 );
}
#endif

[zssgtt]

用va_list这个宏：
va_list vl;
va_start(vl, iErrorNo);
doSomething(vl);
va_end(vl);

[sstower]

这个iErrorNo这哪儿的,代表什么意思?

[snsins]

printf这些函数不就是可变参数的吗？hehe~

[sstower]

楼上没弄懂我的意思,相当于我来实现这个printf,在这个函数中怎样来取它传进来的值