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Unix Network Programming, by W.Richard Stevens / Bill Fenner / Andrew M. Rudoff

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Execute the following from the src/ directory:

./configure    # try to figure out all implementation differences

cd lib # build the basic library that all programs need make # use "gmake" everywhere on BSD/OS systems

cd ../libfree # continue building the basic library make

cd ../libroute # only if your system supports 4.4BSD style routing sockets make # only if your system supports 4.4BSD style routing sockets

cd ../libxti # only if your system supports XTI make # only if your system supports XTI

cd ../intro # build and test a basic client program make daytimetcpcli ./daytimetcpcli

If all that works, you're all set to start compiling individual programs.

Notice that all the source code assumes tabs every 4 columns, not 8.


  1. If you need to make any changes to the "unp.h" header, notice that it is a hard link in each directory, so you only need to change it once.

  2. Go into the "lib/" directory and type "make". This builds the library "libunp.a" that is required by almost all of the programs. There may be compiler warnings (see NOTES below). This step is where you'll find all of your system's dependencies, and you must just update your cf/ files from step 1, rerun "config" and do this step again.

  3. Go into the "libfree/" directory and type "make". This adds to the "libunp.a" library. The files in this directory do not #include the "unp.h" header, as people may want to use these functions independent of the book's examples.

  4. Once the library is made from steps 5 and 6, you can then go into any of the source code directories and make whatever program you are interested in. Note that the horizontal rules at the beginning and end of each program listing in the book contain the directory name and filename.

    BEWARE: Not all programs in each directory will compile on all systems (e.g., the file src/advio/recvfromflags.c will not compile unless your system supports the IP_RECVDSTADDR socket option). Also, not all files in each directory are included in the book. Beware of any files with "test" in the filename: they are probably a quick test program that I wrote to check something, and may or may not work.


  • Many systems do not have correct function prototypes for the socket functions, and this can cause many warnings during compilation. For example, Solaris 2.5 omits the "const" from the 2nd argument to connect(). Lots of systems use "int" for the length of socket address structures, while Posix.1g specifies "size_t". Lots of systems still have the pointer argument to [sg]etsockopt() as a "char *" instead of a "void *", and this also causes warnings.

  • SunOS 4.1.x: If you are using Sun's acc compiler, you need to run the configure program as

    CC=acc CFLAGS=-w CPPFLAGS=-w ./configure

Failure to do this results in numerous system headers () not being found during configuration, causing compile errors later.

  • If your system supports IPv6 and you want to run the examples in the book using hostnames, you must install the latest BIND release. You can get it from All you need from this release is a resolver library that you should then add to the LDLIBS and LDLIBS_THREADS lines.

  • IPv6 support is still in its infancy. There may be differences between the IPv6 sockets API specifications and what the vendor provides. This may require hand tweaking, but should get better over time.

  • If your system supports an older draft of the Posix pthreads standard, but configure detects the support of pthreads, you will have to disable this by hand. Digital Unix V3.2C has this problem, for example, as it supports draft 4, not the final draft.

To fix this, remove wrappthread.o from LIB_OBJS in "Make.defines" and don't try to build and run any of the threads programs.


These are the common differences that I see in various headers that are not "yet" at the level of Posix.1g or X/Open XNS Issue 5.

  • getsockopt() and setsockopt(): 5th argument is not correct type.

  • t_bind(): second argument is missing "const".

  • t_connect(): second argument is missing "const".

  • t_open(): first argument is missing "const".

  • t_optmsmg(): second argument is missing "const".

  • If your defines the members of the topthdr{} as longs, instead of tuscalar_t, some of the printf formats of these value might generate warnings from your compiler, since you are printing a long without a corresponding long format specifier.

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