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The find version of my slackware 10.2 is : GNU find version 4.1.7

I just looked it up, the -L option has been introduced to find in late 2004. I think that it is reasonable nowadays that one could have a find installed that has this option.

To work around this you can remove the -L option in l4/pkg/Makefile, it will work nevertheless for you. Another solution is to update the find package. the find version more than 4.2.28 is ok. You could download the new find package from this link (http://ftp.gnu.org/pub/gnu/findutils/). Thanks. Cheng Guanghui