Go to the first, previous, next, last section, table of contents.
Since it is generally easier to start with a simple example than it is to look at the options that AutoGen uses itself, here is a very simple AutoOpts example. You can copy this example out of the Info file and into a source file to try it. You can then embellish it into what you really need.
Assume you have a program named check
that takes
two options:
check
does.
You want this option available as a POSIX-style flag option
and a GNU long option. You want to allow as many of these
as the user wishes.
First, specify your program attributes and its options to AutoOpts, as with the following example.
AutoGen Definitions options; prog-name = check; prog-title = "Checkout Automated Options"; long-opts; test_main; flag = { name = check_dirs; value = L; /* flag style option character */ arg_type = string; /* option argument indication */ max = NOLIMIT; /* occurrence limit (none) */ stack_arg; /* save opt args in a stack */ descrip = "Checkout directory list"; }; flag = { name = show_defs; descrip = "Show the definition tree"; disable = dont; /* mark as enable/disable type */ /* option. Disable as `dont-' */ };
Then perform the following steps:
autogen -L $prefix/share/autogen checkopt.def
cc -o check -DTEST_CHECK_OPTS -g checkopt.c -L $prefix/lib -lopts
And now, ./check --help
yields:
check - Checkout Automated Options USAGE: check [-<flag> [<val>]]... [--<name>[{=| }<val>]]... Flg Arg Option-Name Description -L YES check-dirs Checkout directory list - may appear without limit no show-defs Show the definition tree - disabled as --dont-show-defs -? no help Display usage information and exit -! no more-help Extended usage information passed thru pager Options may be specified by doubled markers and their name or by a single marker and the flag character/option value.
Normally, however, you would compile `checkopt.c' as in:
cc -o checkopt.o -I$prefix/include -c checkopt.c
and link `checkopt.o' with the rest of your program.
The main program causes the options to be processed
by calling optionProcess
:
main( int argc, char** argv ) { { int optct = optionProcess( &checkOptions, argc, argv ); argc -= optct; argv += optct; }
The options are tested and used as in the following fragment:
if (HAVE_OPT( SHOW_DEFS ) && HAVE_OPT( CHECK_DIRS )) { int dirct = STACKCT_OPT( CHECK_DIRS ); char** dirs = STACKLST_OPT( CHECK_DIRS ); while (dirct-- > 0) { char* dir = *dirs++; ...
A lot of magic happens to make this happen. The rest of this chapter will describe the myriad of option attributes supported by AutoOpts. However, keep in mind that, in general, you won't need much more than what was described in this "quick start" section.
Go to the first, previous, next, last section, table of contents.