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diff --git a/examples/loadables/README b/examples/loadables/README new file mode 100644 index 0000000..6820c96 --- /dev/null +++ b/examples/loadables/README @@ -0,0 +1,76 @@ +Some examples of ready-to-dynamic-load builtins. Most of the +examples given are reimplementations of standard commands whose +execution time is dominated by process startup time. The +exceptions are sleep, which allows you to sleep for fractions +of a second, finfo, which provides access to the rest of the +elements of the `stat' structure that `test' doesn't let you +see, and pushd/popd/dirs, which allows you to compile them out +of the shell. + +All of the new builtins in ksh93 that bash didn't already have +are included here, as is the ksh `print' builtin. + +The configure script in the top-level source directory uses the +support/shobj-conf script to set the right values in the Makefile, +so you should not need to change the Makefile. If your system +is not supported by support/shobj-conf, and it has the necessary +facilities for building shared objects and support for the +dlopen/dlsyn/dlclose/dlerror family of functions, please make +the necessary changes to support/shobj-conf and send the changes +to bash-maintainers@gnu.org. + +Loadable builtins are loaded into a running shell with + + enable -f filename builtin-name + +enable uses a simple reference-counting scheme to avoid unloading a +shared object that implements more than one loadable builtin before +all loadable builtins implemented in the object are removed. + +Many of the details needed by builtin writers are found in hello.c, +the canonical example. There is no real `builtin writers' programming +guide'. The file template.c provides a template to use for creating +new loadable builtins. + +The file "Makefile.inc" is created using the same values that configure +writes into Makefile.in, and is installed in the same directory as the +rest of the example builtins. It's intended to be a start at something +that can be modified or included to help you build your own loadables +without having to search for the right CFLAGS and LDFLAGS. + +basename.c Return non-directory portion of pathname. +cat.c cat(1) replacement with no options - the way cat was intended. +dirname.c Return directory portion of pathname. +fdflags.c Change the flag associated with one of bash's open file descriptors. +finfo.c Print file info. +head.c Copy first part of files. +hello.c Obligatory "Hello World" / sample loadable. +id.c POSIX.2 user identity. +ln.c Make links. +loadables.h File loadable builtins can include for shell definitions. +logname.c Print login name of current user. +Makefile.in Simple makefile for the sample loadable builtins. +Makefile.inc.in Sample makefile to use for loadable builtin development. +mkdir.c Make directories. +mypid.c Add $MYPID variable, demonstrate use of unload hook functio.n +necho.c echo without options or argument interpretation. +pathchk.c Check pathnames for validity and portability. +print.c Loadable ksh-93 style print builtin. +printenv.c Minimal builtin clone of BSD printenv(1). +push.c Anyone remember TOPS-20? +realpath.c Canonicalize pathnames, resolving symlinks. +rm.c Remove files and directories. +rmdir.c Remove directory. +seq.c Print a sequence of decimal or floating point numbers. +setpgid.c Set a process's pgrp; example of how to wrap a system call. +sleep.c sleep for fractions of a second. +stat.c populate an associative array with information about a file +strftime.c Loadable builtin interface to strftime(3). +sync.c Sync the disks by forcing pending filesystem writes to complete. +tee.c Duplicate standard input. +template.c Example template for loadable builtin. +truefalse.c True and false builtins. +tty.c Return terminal name. +uname.c Print system information. +unlink.c Remove a directory entry. +whoami.c Print out username of current user. |