Speaking as somebody with over 10 years UNIX programming experience ...
 
There is a heck of a lot more to POSIX then learning some simple file
manipulation commands.  It is like feeling that you are qualified to fly
an airplane because you know how to get to the airport.  :-)
 
Seriously, may I suggest a book entitled, "the POSIX Programmers Guide",
by
Donald Lewine.  ISBN 0-937175-73-0.  The book assumes you are a qualified
C
programmer, and you are familiar with issues involving a multi-user
environment.
 
The chapters include:
        Introduction to POSIX
        Writing a POSIX-compliant program, the basics.
        Input/output facilities of the standard C library
        The file system as defined by POSIX Operations of POSIX.
        I/O, pipes, FIFOs
        Creating and terminationg processes and signals
        Obtaining information about the environment
        Communication line settings
        POSIX and Standard C, including features and portability pitfalls
        Internationalization
        Reference sesctions (library functions, data structures, error codes
...)
 
As you can see, getting up on "POSIX", represents a serious undertaking,
but
yields appropriate awards.
 
David Lethe
VP - UNIX Division
Datasys Computer Corp.
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