ref: 3d0363a586d0812f5b1dc610fba3b3cd0b79f0e1 dir: /examples/username.peg/
%{ #include <unistd.h> %} start = "username" { printf("%s", getlogin()); } | < . > { putchar(yytext[0]); } %% int main() { while (yyparse()); return 0; }