httpd-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Rasmus Lerdorf <>
Subject Re: apache 2.0 config language
Date Sat, 25 Oct 1997 04:57:27 GMT
> Folks may remember my proposed new language, which I wanted to parse with
> yacc/bison.  Problem:  yacc is not thread safe. 
> bison is supposedly thread-safe, but last I tried I had to actually patch
> the source to get it to work right.

Making a Bison parser thread-safe isn't too bad.  Making a flex scanner
thread-safe is a lot more difficult unless you use flex++ and thus c++.

> While bison itself is GPL, its output isn't.  However if we've patched it,
> then we're limited by GPL a bit.  We can use simple.h and hairy.h (the
> bison engines which actually use the tables output by bison) *unmodified*
> without being affected by GPL, but ... we have to modify them to get
> thread-safe code. 

This is not the case.  It was the case once, but that is well over a year
ago.  The current Bison info file has the following paragraph:

   As of Bison version 1.24, we have changed the distribution terms for
   `yyparse' to permit using Bison's output in non-free programs.
   Formerly, Bison parsers could be used only in programs that were free


View raw message