| 1 | Some examples of ready-to-dynamic-load builtins. Most of the
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| 2 | examples given are reimplementations of standard commands whose
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| 3 | execution time is dominated by process startup time. The
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| 4 | exceptions are sleep, which allows you to sleep for fractions
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| 5 | of a second, finfo, which provides access to the rest of the
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| 6 | elements of the `stat' structure that `test' doesn't let you
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| 7 | see, and pushd/popd/dirs, which allows you to compile them out
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| 8 | of the shell.
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| 9 |
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| 10 | All of the new builtins in ksh93 that bash didn't already have
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| 11 | are included here, as is the ksh `print' builtin.
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| 12 |
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| 13 | The configure script in the top-level source directory uses the
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| 14 | support/shobj-conf script to set the right values in the Makefile,
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| 15 | so you should not need to change the Makefile. If your system
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| 16 | is not supported by support/shobj-conf, and it has the necessary
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| 17 | facilities for building shared objects and support for the
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| 18 | dlopen/dlsyn/dlclose/dlerror family of functions, please make
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| 19 | the necessary changes to support/shobj-conf and send the changes
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| 20 | to bash-maintainers@gnu.org.
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| 21 |
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| 22 | Loadable builtins are loaded into a running shell with
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| 23 |
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| 24 | enable -f filename builtin-name
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| 25 |
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| 26 | enable uses a simple reference-counting scheme to avoid unloading a
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| 27 | shared object that implements more than one loadable builtin before
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| 28 | all loadable builtins implemented in the object are removed.
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| 29 |
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| 30 | Many of the details needed by builtin writers are found in hello.c,
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| 31 | the canonical example. There is no real `builtin writers' programming
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| 32 | guide'. The file template.c provides a template to use for creating
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| 33 | new loadable builtins.
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