c / expert
Snippet
Variadic Function Argument Forwarding via va_list Traversal
C provides standard macros in stdarg.h to receive variable argument counts. The va_list type tracks argument state, va_start initializes pointer positions after mandatory parameters, vprintf handles formatted output, and va_end ensures clean stack frame teardown.
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#include <stdio.h>#include <stdarg.h>void log_message(const char *level, const char *fmt, ...) {va_list args;va_start(args, fmt);printf("[%s] ", level);vprintf(fmt, args);va_end(args);printf("\n");}
Breakdown
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va_list args;
Declares an internal argument pointer structure to maintain parameter iteration state.
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va_start(args, fmt);
Binds va_list to start traversing arguments immediately following the mandatory parameter fmt.
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vprintf(fmt, args);
Delegates formatted printing to vprintf using the initialized va_list parameter packet.
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va_end(args);
Cleans up memory state associated with va_list before leaving function scope.