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%{
#include <unistd.h>
%}

start =	"username"	{ printf("%s", getlogin()); }
|	< . >		{ putchar(yytext[0]); }

%%

int main()
{
  GREG g;
  yyinit(&g);
  while (yyparse(&g));
  yydeinit(&g);
  return 0;
}