From 82ba818ff456bcd6d56a06226e3f27e98fbb55c3 Mon Sep 17 00:00:00 2001 From: Craig Jennings Date: Thu, 14 Aug 2025 22:58:58 -0500 Subject: removing all downloaded devdocs files --- devdocs/c/variadic%2Fva_copy.html | 56 --------------------------------------- 1 file changed, 56 deletions(-) delete mode 100644 devdocs/c/variadic%2Fva_copy.html (limited to 'devdocs/c/variadic%2Fva_copy.html') diff --git a/devdocs/c/variadic%2Fva_copy.html b/devdocs/c/variadic%2Fva_copy.html deleted file mode 100644 index fe57eb4c..00000000 --- a/devdocs/c/variadic%2Fva_copy.html +++ /dev/null @@ -1,56 +0,0 @@ -

va_copy

Defined in header <stdarg.h> 
void va_copy( va_list dest, va_list src );
-		 (since C99)

The va_copy macro copies src to dest.

-

va_end should be called on dest before the function returns or any subsequent re-initialization of dest (via calls to va_start or va_copy).

-

Parameters

- - -
dest - an instance of the va_list type to initialize
src - the source va_list that will be used to initialize dest

Expanded value

(none)

-

Example

#include <stdio.h>
-#include <stdarg.h>
-#include <math.h>
- 
-double sample_stddev(int count, ...) 
-{
-    /* Compute the mean with args1. */
-    double sum = 0;
-    va_list args1;
-    va_start(args1, count);
-    va_list args2;
-    va_copy(args2, args1);   /* copy va_list object */
-    for (int i = 0; i < count; ++i) {
-        double num = va_arg(args1, double);
-        sum += num;
-    }
-    va_end(args1);
-    double mean = sum / count;
- 
-    /* Compute standard deviation with args2 and mean. */
-    double sum_sq_diff = 0;
-    for (int i = 0; i < count; ++i) {
-        double num = va_arg(args2, double);
-        sum_sq_diff += (num-mean) * (num-mean);
-    }
-    va_end(args2);
-    return sqrt(sum_sq_diff / count);
-}
- 
-int main(void) 
-{
-    printf("%f\n", sample_stddev(4, 25.0, 27.3, 26.9, 25.7));
-}

Possible output:

-
0.920258

References

See also

- - - - -
accesses the next variadic function argument
(function macro)
ends traversal of the variadic function arguments
(function macro)
holds the information needed by va_start, va_arg, va_end, and va_copy
(typedef)
enables access to variadic function arguments
(function macro)
C++ documentation for va_copy
-

- © cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
- https://en.cppreference.com/w/c/variadic/va_copy -

-
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