7.9 Using AutoOpts

There are actually several levels of using autoopts. Which you choose depends upon how you plan to distribute (or not) your application.

7.9.1 local-only use

To use AutoOpts in your application where you do not have to worry about distribution issues, your issues are simple and few.

• Create a file ‘myopts.def’, according to the documentation above. It is probably easiest to start with the example in Quick Start and edit it into the form you need.
• Run AutoGen to create the option interface file (myopts.h) and the option descriptor code (myopts.c):

  autogen myopts.def

• In all your source files where you need to refer to option state, #include "myopts.h".
• In your main routine, code something along the lines of:

  #define ARGC_MIN some-lower-limit #define ARGC_MAX some-upper-limit main( int argc, char** argv ) { { int arg_ct = optionProcess( &myprogOptions, argc, argv ); argc -= arg_ct; if ((argc < ARGC_MIN) || (argc > ARGC_MAX)) { fprintf( stderr, "%s ERROR: remaining args (%d) " "out of range\n", myprogOptions.pzProgName, argc ); USAGE( EXIT_FAILURE ); } argv += arg_ct; } if (HAVE_OPT(OPTN_NAME)) respond_to_optn_name(); ... }

• Compile ‘myopts.c’ and link your program with the following additional arguments:

  `autoopts-config cflags ldflags` myopts.c

7.9.2 binary distro, AutoOpts not installed

If you will be distributing (or copying) your project to a system that does not have AutoOpts installed, you will need to statically link the AutoOpts library, libopts into your program. Get the link information with static-libs instead of ldflags:

`autoopts-config static-libs`

7.9.3 binary distro, AutoOpts pre-installed

If you will be distributing (or copying) your project to a system that does have AutoOpts (or only libopts) installed, you will still need to ensure that the library is findable at program load time, or you will still have to statically link. The former can be accomplished by linking your project with ‘--rpath’ or by setting the LD_LIBRARY_PATH appropriately. Otherwise, See section binary distro, AutoOpts not installed.

7.9.4 source distro, AutoOpts pre-installed

If you will be distributing your project to a system that will build your product but it may not be pre-installed with AutoOpts, you will need to do some configuration checking before you start the build. Assuming you are willing to fail the build if AutoOpts has not been installed, you will still need to do a little work.

AutoOpts is distributed with a configuration check M4 script, ‘autoopts.m4’. It will add an autoconf macro named, AG_PATH_AUTOOPTS. Add this to your ‘configure.ac’ script and use the following substitution values:

AUTOGEN

the name of the autogen executable

AUTOGEN_TPLIB

the directory where AutoGen template library is stored

AUTOOPTS_CFLAGS

the compile time options needed to find the AutoOpts headers

AUTOOPTS_LIBS

the link options required to access the libopts library

7.9.5 source distro, AutoOpts not installed

If you will be distributing your project to a system that will build your product but it may not be pre-installed with AutoOpts, you may wish to incorporate the sources for libopts in your project. To do this, I recommend reading the tear-off libopts library ‘README’ that you can find in the ‘pkg/libopts’ directory. You can also examine an example package (blocksort) that incorporates this tear off library in the autogen distribution directory. There is also a web page that describes what you need to do:

http://autogen.sourceforge.net/blocksort.html

Alternatively, you can pull the libopts library sources into a build directory and build it for installation along with your package. This can be done approximately as follows:

tar -xzvf `autoopts-config libsrc`
cd libopts-*
./bootstrap
configure
make
make install

That will install the library, but not the headers or anything else.

This document was generated by Bruce Korb on August 21, 2015 using texi2html 1.82.