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+{{keywords>wiki library source code example reference}}
+====== vfprintf ======
+<code c>
+int vfprintf(FILE *stream, const char *format, va_list arg);
+</code>
+Equivalent to fprintf with variable argument list replaced by arg, which must have been initialised by the va_start macro (and may have been used in calls to va_arg).
+===== C Sourcecode Example =====
+<code c>
+/*
+ * vfprintf example code
+ * http://code-reference.com/c/stdio.h/vfprintf
+ */
+#include <stdio.h> /* including standard library */
+//#include <windows.h> /* uncomment this for Windows */
+#include <stdarg.h>
+int myfprintf( FILE *file, char const * format, ... )
+{
+  va_list args;
+  int n;
+  va_start( args, format );
+  n=vfprintf( file, format, args );
+  va_end( args );
+  fputs("vfprintf test line\n", file);
+  return n;
+}
+int main (void)
+{
+  char string[] ="Hello";
+  FILE * stream = fopen("test.txt","w");
+  if(stream == 0) {
+   perror("file problem");
+  }
+   myfprintf( stream, " %s World\n", string);
+   fclose(stream);
+   return 0;
+}
+</code>
+==== output ====
+== test.txt ==
+<code c>
+Hello World
+vfprintf test line
+</code>

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