ref: 63f3a973ef06a5ce4f7a93cc6c99bb6eaab08e11 dir: /examples/username.peg/
%{ #include <unistd.h> %} start = "username" { printf("%s", getlogin()); } | < . > { putchar(yytext[0]); } %% int main() { while (yyparse()); return 0; }