New features with AN-2021-05-19:

This is the first localization step for the schily source consolidation. Many
programs now (hopefully) call gettext() for all strings that need localization.

-	The next step will include dgettext() calls for the libraries and the
	missing programs

-	The following step will include the extracted strings

-	The last step will include German translations and install support
	for the resulting binary message object files.

----------> Please test and report compilation problems! <---------

***** NOTE: As mentioned since 2004, frontends to the tools should *****
*****		call all programs in the "C" locale		   *****
*****		by e.g. calling: LC_ALL=C cdrecord ....		   *****
*****		unless these frontends support localized strings   *****
*****		used by the cdrtools with NLS support.		   *****

		*** WARNING        ***
		*** Need new smake ***

	*** Due to the fact that schily-tools 2014-04-03 introduced to use new macro
	*** expansions and a related bug fix in smake, you need a newer smake
	*** to compile this source. If your smake is too old and aborts, ensure to
	*** use the recent smake by calling:

	cd ./psmake
	./MAKE-all
	cd ..
	psmake/smake
	psmake/smake install

	The new smake version mentioned above is smake-1.2.4
	The recent smake version is smake-1.3

	*** Due to the fact that schily-tools 2018-01-26 introduced
	*** optimizations for the Schily version of SunPro Make, you
	*** need at least the dmake version from 2018/01/11 with support
	*** for the "export" directive to compile with this makefile system.

For the beginning of the list of new features of the software in this tarball, 
please scroll down to "NEW FEATURES"

	WARNING: the new version of the isoinfo program makes use of the 
		*at() series of functions that have been introduced by Sun
		in August 2001 and added to POSIX.1-2008. For older platforms,
		libschily now includes emulations for these functions but
		these emulations have not yet been tested thoroughly.
		Please report problems!

	BUG WARNING: Please never report bugs only to Linux distributions as
		they usually do not forward these bug reports upstream and as
		the Linux distributions typically do not let skilled people
		check the bugs. We did not hear about a FIFO problem in star
		for a long time. Then a problem on Linux occurred once
		every 6000-10000 tries but it did not happen on Solaris after
		even 10 million tries, so it was not known besides Linux.

	BUG WARNING: *** GNU make *** starts too early with parallel
		execution (when reading Makefiles and evaluating rules for
		"include" statements already). Since GNU make does not
		support a concept for a correct ordering of such actions,
		you need to be prepared to see gmake fail in parallel
		mode. If you are interested in reliable parallel execution,
		it is recommended to use the included "dmake" program with
		a command line like:

			dmake -j10 -f SMakefile

		from the top level directory. Note that if you are on Linux,
		you need a halfway recent kernel or the compile time will not
		go down because of the low POSIX semaphore performance in
		older Linux kernels.

		The "dmake" program included in the schilytools tarball is the
		current version of the "new" SunOS make program that has been
		introduced in January 1986 by Sun Microsystems. It also
		introduced new features like the "include" directive that
		3 years later have been copied by gmake in a partially buggy
		way. As gmake does not fix showstopper bugs, it cannot be
		supported. Current showstoppers are: 1) gmake executes
		"include" related rules in the inverse order, causing rules
		to fail if they depend on files created by an "earlier" action
		2) gmake caches an outdated state of the directory and aborts
		with a wrong complain about allegedly missing files that in
		fact exist already.

NEW FEATURES:

-	Schily.Copyright has been updated to match the current state.

-	Symlink based support for the platform "arm-freebsd" has been added to
	the script RULES/MKLINKS.

	Thanks to Robert Clausecker for reporting

-	.links: Added the names of the symlinks from the above additions
	to permit to auto-remove all symlinks that are auto-created.

-	Makefilesystem: Added a new make macro definition NOECHO=@ to the
	central rules file RULES/rules.top

-	Makefilesystem: based on the NOECHO=@ definition, all RULES/* files have
	been modified to use $(NOECHO) instead of <TAB>@ in make rule commands.
	This allows to call:

		make NOECHO=

	to disable the "noecho mode" (which is the default in the schily makefile
	system) with all supported make implementations (not only smake) in rule
	commands to make commands fully visible for debug purposes.

	NOECHO= is forwarded to sub-makes, so if you like to switch into echo
	mode, simply call make NOECHO= from the top level directory.

-	README.compile now explains NOECHO= and how to use it.

-	README.compile now explains CCC=xxx for modified compilers.

-	README.compile now explains how to use CCC=xxx to enable clang based
	AFL (American fuzzy Lop) usage.

-	README.compile introduced various typo corrections from Heiko Eifeldt.

-	autoconf: A new autoconf test for the availability of support for

		__attribute__ ((__noinline__))

	in the current compiler has been added.

-	include/schily/ccomdefs.h: support for the new autoconf test 
	for __attribute__ ((__noinline__)) has been added via a new 
	#define __NO_INL__

	This permits to use this feature even if the compiler does not
	support it. In the latter case, __NO_INL__ acts as a no-op.

-	makefiles.tar.bz2: updated to match the current Makefilesystem
	state.

-	libschily/getfp.c and inc/getfp.c now use the __noinline__
	attributev ia __NO_INL__ since getfp.c may be used via
	#include "getfp.c"

-	inc/avoffset.c now uses "volatile struct frame *fp;" in hope to
	advise compilers to be less nasty.

-	Bourne Shell: The "ERR" trap is now also triggered in case that
	the error is of type "command not found" or "cannot execute".

	Before, the "ERR" trap was only triggered in case that a normal
	program (executed via fork()/exec()) did cause a normal exit()
	based exit code that was non-zero.

-	Bourne Shell: the fc(1) builtin now handles "fc -l -0" the same
	way as ksh does and refers to the current command. Before only
	"fc -l -1" did work to select the previous command.

	Together with the "ERR" trap fix, this permits to install a 
	"command not found" handler in the shell that could explain users
	how to install a missing command.

	This "missing command" handler could be implemented via:

	  trap 'show-info-message-for-missing-command $(fc -l -0)' ERR

-	SunPro Make: Macros created with ::= are now implemented as a different
	macro type (GNU assign macros) and no longer expanded when they are
	used in a make rule command.

-	SunPro Make: Macros created with ::= are now implemented as a different
	macro type (GNU assign macros) and no longer expanded when they are
	used to the left or right side of a dependency rule.

	This finally lets SunPro Make fully support the idiosyncratic way,
	GNU make implements ::= based macro assignments.

-	SunPro Make: The man page now mentions the new operators +:= and :::=
	that have been introduced with schilytools-2021-04-21, but fogotten
	to document then.

-	SunPro Make: Command line macros now may use the ::=, :::= and
	+:= operator.

	Only command line macros assigned via ::= and :::= are forwarded
	to sub-make programs. This is aligned with the previous behavior of
	SunPro Make that did forward "MACRO=value" command line macros but
	did not not forward command line macros that have been modified 
	via the +:= operator as well.

-	SunPro Make: The assignment operators ::= and :::= are now forwarded
	to sub-makes via the MAKEFLAGS environment.

-	SunPro Make: The man page now explains command line macros using
	the ::=, :::=, += and +:= operators.

	Command line macros that use the += operator have been implemented
	by SunPro Make since 1986 but not documented until now.

-	SunPro Make: make -v and make -version now print a new version date.

-	smake: smake "MACRO += value" now works.

	smake did implement command line macros like "MACRO=value" since
	spring 1996 but did not yet support "MACRO +=value" as well.

-	smake: smake "MACRO::=value" "MACRO:::=value", "MACRO +:= value"
	now work as well.

-	smake: The man page now mentions the new command line macro operators
	::=, :::=, += and +:=

-	smake: Version bumped to 1.5


SCCS THOUGHTS:

-	SCCS: The current idea for converting a historic SCCS project into
	a project oriented SCCS history bundle is the following:

	-	Create a user map file for "sccslog" by calling:

		mkdir $HOME/.sccs
		$EDITOR $HOME/.sccs/usermap

		Enter the UNIX login names followed by a TAB, followed
		by an E-mail notation. Use one line per user, e.g.

			joerg	J. Schilling <joerg@mail.com>

	-	Create a copy of the whole project to work on for this test.
		Do not do this conversion on the original project until
		sccs-6.0 is ready.

	-	chdir to the project home directory of the just created copy.

	-	Call "sccs init -i ." to make the project using an in-tree
		project oriented repository.

	-	Call:

		find * -path '*SCCS/s.*' | /opt/schily/ccs/bin/sccscvt -NSCCS/s. -k -ooo -V6 -

		for the CSRG BSD project use:

		find * -path '*SCCS/s.*' | TZ=US/Pacific /opt/schily/ccs/bin/sccscvt -NSCCS/s. -k -ooo -V6 -

		to convert all history files into SCCSv6 history files. The
		TZ=US/Pacific is important for the UCB conversion since SCCSv6
		uses timezones but SCCSv4 does not and we need to have the 
		correct timezone entries in the SCCSv6 history files.

		For the complete "schilytools" project with 4200 SCCS history
		files in 55 Mbytes, this takes 12 seconds for the SCCS history
		from 1984 .. 2020, but note that most of the edits from the
		1980s are lost, so there are few entries from the time
		before 1989.

		An alternate example: the SCCS history from the BSD-4.4 project
		from December 1979 up to June 1995 is in 12600 SCCS history
		files that take up 125 MB.
		The conversion time to the SCCSv6 history file format is
		18 seconds.

	-	Call:

		find * -path '*SCCS/s.*' | /opt/schily/ccs/bin/sccslog -changeset -

		to populate the changeset file from the existing deltas.

		For the complete "schilytools" project with 19600 commits,
		this takes 8 minutes. The resulting file .sccs/SCCS/s.changeset
		has a size of approx. 7 MBytes.

		An alternate example: the SCCS history from the BSD-4.4 project
		from December 1979 up to June 1995 has approx. 47000 commits.
		The conversion time is approx. 40 minutes.
		The size of the resulting changeset file is approx. 14 MBytes.

	-	convert the in-tree repository into an off-tree repository.
		This final step is not yet needed and there is currently no
		code to do that automatically.

	-	If you like to check the resulting changeset file, there is
		currently only one way to look at it, by calling:

		sccs -O get -p -A -m .sccs/SCCS/s.changeset | more

		This prints an annotated version of the changeset file.
		The next task is to develop an enhancement to "sccs log"
		that prints the changeset in a way similar to what "hg log -v"
		prints.

	-	NOTE: Normal filesystems on Linux are slow, it is advised to
		make the conversions on tmpfs for performance reasons in case
		you are using Linux.

	Please however keep in mind that this is still experimental and there is
	absolutely no grant that a changelog created with current experimental
	software will work correctly with the final SCCS version. The procedure
	is just an example to check how it may look like.

	The final conversion method will be more automated... most likely
	by a command similar to "sccs import ..."

	IMPORTANT: This is not yet the time to finally convert a project into
	the project mode, because the project would be stuck in the current 
	state. What we need to continue work in that repository state in the
	project mode is at least a working "sccs commit". Be prepared to remove
	the changeset history file once "sccs commit" works and to re-create
	the changeset file for that time.

 

-	SCCS TODO:

	-	Activate "fsdiff" as a "bdiff" replacement in delta(1)
		to speed up delta(1) and to reduce the size of the SCCS
		history files.

	-	Implement something that outputs similar information from
		the changeset file as printed with "hg log -v".

		This would be the next key feature.

	-	verify whether sccs.c uses -NSCCS in the back end programs
		correctly, instead of converting g-file names from the command
		line into s.file names in the frontend in order to forward 
		s.file names to the backend programs. This is needed for an
		off-tree repository.

		The related unit tests are already passed.

	-	Add code to to sccs(1) to send a list of files to admin(1) and
		delta(1) with new or modified files in order to have all
		important code for a "sccs commit" in a single program that
		does not need to deal with ARG_MAX limitations.

	-	Add code to admin(1), delta(1), sccs-log(1) and get(1) to 
		maintain/understand the changeset file.

		This is mainly writing out the sccschangeset(4) entries to an
		intermediate store if a single file has been treated
		successfully. For sccs-log(1), see below.

	-	Finish the work to allow normal line based diffs in SCCS even
		for binary files. This are files that include nul bytes and
		this needs to completely avoid fputs() and this needs an 
		initialized member p_line_length in struct packet even for 
		all content that does not result from a previous getline() call.

	-	sccs -R tell (and probably other subcommands?) does not yet
		work in NewMode

	-	Add code to libcomobj to understand the changeset file.
		This is needed in order to e.g. know the file names and file
		specific SIDs/state that corresponds to a project global SID.

	-	Find/verify a complete transactional model that allows to repair
		complex changes to the set of files for a project that have
		been aborted in the middle. The current idea is to create the
		file $PROJECTHOME/.sccs/changeset with the deltas to the
		changeset during a complex update operation.

	-	Find a decision on how to deal with the admin flags that are
		currently implemented as global flags and thus do not depend on
		the SID (version) if the history file.

	-	Aborting a transaction via ^C currently requires a manual
		removal of the global lock file. Find a way to avoid this in
		case that a commit has been aborted while being prompted for
		a commit message (which is before any real action happened).

	-	Implement a fully automated method to convert a SCCSv4 based
		history with unrelated history files into a new SCCSv6 based
		project mode history with a populated changeset history file.

		This will most likely be done as a variant of the to be defined
		new command "sccs sccsimport" that imports a whole existing old
		SCCS project.

	-	Implement this "sccs sccsimport" based conversion in a way where
		sccs(1) holds the global changeset lock for the whole time
		of the conversion.




-	Bourne Shell Missing features for POSIX compliance:

	- Support for $'...' quoting (this is not needed for the current
					version of POSIX but for the next POSIX
					version that will be named SUSv8).
					The development of SUSv8 will start in
					late 2016.

	We are now expecting the Bourne Shell to be fully POSIX compliant.

-	Bourne Shell further TODO list:

	-	Finish loadable builtin support.

	-	POSIX does not allow us to implement ". -h", so we will
		add a "source" builtin to be able to implement "source -h"

-	The following builtins (that are available in bsh) are still missing in
	the Bourne Shell:

	err			echo with output going to stderr
	glob			echo with '\0' instead of ' ' between args
	env			a builtin version of /usr/bin/env

	The following bsh intrinsics are still missing in the Bourne Shell:

	-			the restricted bsh has restriction features that
				are missing in the Bourne shell.

	-	source -h	read file into history but do not execute

	and probably more features not yet identified to be bsh unique.



Author:

Joerg Schilling
D-13353 Berlin
Germany

Email: 	joerg@schily.net

Please mail bugs and suggestions to me.
