bin: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

sh: implement PS1 \D to print current time

\D{format} yields the result of calling strftime(3) with the provided
format and the current time.

When PS4 can use this, it will enable us to easily generate timestamps
when tracing script execution.

Differential Revision: https://reviews.freebsd.org/D35840

Remove $FreeBSD$: one-line nroff pattern

Remove /^\.\\"\s*\$FreeBSD\$$\n/

sh(1): Allow non-printing characters in prompt strings

Introduce new prompt format characters:

- '\[' starts the sequence of non-printing chatacters
- '\]' ends the sequence of non-printing characters

Within these sequences, the following characters are now supported:

- '\a' emits ASCII BEL (0x07, 007) character
- '\e' emits ASCII ESC (0x1b, 033) character
- '\r' emits ASCII CR (0x0d, 015) character
- '\n' emits ASCII CRLF sequence

These can be used to embed ANSI sequences into prompt strings.

Example in .shrc:

PS1="\[\e[7m\]\u@\h\[\e[0m\]:\w \\$ "

This tries to maintain some degree of compatibility with GNU bash,
that uses GNU readline library (which behaves slightly different from
BSD editline): It has two "non-printing boundary" characters:

- RL_PROMPT_START_IGNORE (\001)
- RL_PROMPT_END_IGNORE (\002)

while BSD editline only has one (when using EL_PROMPT_ESC setting), so
for this purpose, ASCII \001 was chosen and both \[ and \] emits
this character.

And while here, enlarge PROMPTLEN from 128 to 192 characters.

Reviewed by: jilles
Approved by: jilles
Differential Revision: https://reviews.freebsd.org/D37701

For man page references found in ports, indicate the respective port.

sh.1: Fix a mandoc warning

- new sentence, new line

MFC after: 3 days

sh: Add -o verify to use O_VERIFY when sourcing scripts

Add -o verify to sh to make it use O_VERIFY when
sourcing scripts and reading profiles.

Useful in conjunction with mac_veriexec to help protect at
least some parts of the boot sequence, e.g., /etc/rc*.

Differential revision: https://reviews.freebsd.org/D30464
Reviewed by: jilles, sjg
Obtained from: Stormshield

sh: implement persistent history storage

Implement persistent history storage:
the strategy is simple at start: loads the existing .sh_history file
at exit dump it.

The implementation respects the HISTFILE variable and its POSIX
definition: ~/.sh_history is used if HISTFILE is not set.

to avoid sh to create the history file, set HISTSIZE to 0 or HISTFILE to
en empty value

Co-authored-by: pstef
Reviewed by: jilles
Differential Revision: https://reviews.freebsd.org/D29493

Fix description of the "\$" sequence for PS1

The manual page documents "\$" to expand to either "$" or "#" followed by
a single space. In reality, the single space character is not appended.

PR: 247791
Submitted by: kd-dev@pm.me
MFC after: 7 days

sh: Add set -o pipefail

The pipefail option allows checking the exit status of all commands in a
pipeline more easily, at a limited cost of complexity in sh itself. It works
similarly to the option in bash, ksh93 and mksh.

Like ksh93 and unlike bash and mksh, the state of the option is saved when a
pipeline is started. Therefore, even in the case of commands like
A | B &
a later change of the option does not change the exit status, the same way
(A | B) &
works.

Since SIGPIPE is not handled specially, more work in the script is required
for a proper exit status for pipelines containing commands such as head that
may terminate successfully without reading all input. This can be something
like

(
cmd1
r=$?
if [ "$r" -gt 128 ] && [ "$(kill -l "$r")" = PIPE ]; then
exit 0
else
exit "$r"
fi
) | head

PR: 224270
Relnotes: yes

Make sh(1) support \u in PS1. This removes one fork/exec on interactive
shell startup.

Reviewed by: 0mp (man page), jilles
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D18790

sh(1): Remove -c string from set builtin documentation

Altering the -c string at run time does not make sense and is not possible.

MFC after: 1 week

sh: Use 126 and 127 exit status for failures opening a script

This affects scripts named on the command line, named with a '.' special
builtin and found via the PATH %func autoloading mechanism.

PR: 231986

Describe how to prevent *.core files from being created using ulimit.

While here, pet mandoc.

Reviewed by: eadler (previous revision), jilles (previous revision), mat (mentor)
Approved by: manpages (jilles), mat (mentor)
Differential Revision: https://reviews.freebsd.org/D15609

sh(1): Markup and spelling fixes

Fix mandoc -Tlint warnings in bin/

Many style-level issues are still reported.

Submitted by: Yuri Pankov <yuripv@gmx.com>
Reviewed by: jilles (previous revision)
Differential Revision: https://reviews.freebsd.org/D13334

sh: Ignore error when cd writes the directory actually switched to.

If CDPATH is used non-trivially or the operand is "-", cd writes the
directory actually switched to. (We currently do this only in interactive
shells, but POSIX requires this in non-interactive shells as well.)

As mentioned in Austin group bug #1045, cd shall not return an error while
leaving the current directory changed. Therefore, ignore any write error.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Remove empty Li

Reported by: make manlint
MFC after: 2 days

sh: Do not import IFS's value from the environment.

Per Austin group issue #884, always set IFS to $' \t\n'. As before, IFS will
be exported iff it was in the environment.

Most shells (e.g. bash, ksh93 and mksh) already did this. This change
improves predictability, in that scripts can simply rely on the default
value.

However, the effect on security is little, since applications should not be
calling the shell with attacker-controlled environment variable names in the
first place and other security-sensitive variables such as PATH should be
and are imported by the shell.

When using a new sh with an old (before 10.2) libc wordexp(), IFS is no
longer passed on. Otherwise, wordexp() continues to pass along IFS from the
environment per its documentation.

Discussed with: pfg
Relnotes: yes

Clarify the explanations for the hostname and FQDN entries.

MFC after: 1 week

Match the descriptions of the \H and \h prompt string sequences to reality.
They were swapped.

X-Confirmed by: jilles
MFC after: 1 week

Fix handling of umtxp resource limit in sh(1)/ulimit(1), limits(1), add
login.conf(5) support.

Reviewed by: jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D5610

sh(1): Document 'cd -'.

This reflects the changes in r294649 and can therefore not be MFCed by
itself.

sh: Add set -o nolog.

POSIX requires this to prevent entering function definitions in history but
this implementation does nothing except retain the option's value. In ksh88,
function definitions were usually entered in the history file, even when
they came from ~/.profile and the $ENV file, to allow displaying their
definitions.

This is also the first option that does not have a letter.

sh(1): libedit has supported multibyte encodings for a while.

sh: Fix the trap builtin to be POSIX-compliant for 'trap exit SIG' and 'trap n n...'.

The parser considered 'trap exit INT' to reset the default for both EXIT and
INT. This beahvior is not POSIX compliant. This was avoided if a value was
specified for 'exit', but then disallows exiting with the signal received. A
possible workaround is using ' exit'.

However POSIX does allow this type of behavior if the parameters are all
integers. Fix the handling for this and clarify its support in the manpage
since it is specifically allowed by POSIX.

Differential Revision: https://reviews.freebsd.org/D2325
Reviewed by: jilles
MFC after: 2 weeks

sh: Add details about importing the environment and initializing OPTIND.

sh(1): Add/improve information about exit status of commands.

sh(1): Mention portability issue with shifting zero positional parameters.

Per Austin Group issue #459, shifting zero positional parameters may or may
not be considered an operand error (which causes the shell to exit in most
cases).

sh(1): Clarify that assignments before commands do not affect expansions.

PR: 193759
MFC after: 1 week

sh: Allow enabling job control without a tty in non-interactive mode.

If no tty is available, 'set -m' is still useful to put jobs in their own
process groups.

sh: Add -h option to SYNOPSIS

Reviewed by: jilles
MFC after: soon

sh: Allow aliases to force alias substitution on the following word.

If an alias's value ends with a space or tab, the next word is also
checked for aliases.

This is a POSIX feature. It is useful with utilities like command and
nohup (alias them to themselves followed by a space).

sh(1): Discourage use of -e.

Also, do not say that ! before a pipeline is an operator, because it is
syntactically a keyword.

sh(1),limits(1): Document kqueues (-k) rlimit.

sh: Make return return from the closest function or dot script.

Formerly, return always returned from a function if it was called from a
function, even if there was a closer dot script. This was for compatibility
with the Bourne shell which only allowed returning from functions.

Other modern shells and POSIX return from the function or the dot script,
whichever is closest.

Git 1.8.4's rebase --continue depends on the POSIX behaviour.

Reported by: Christoph Mallon, avg

sh(1): A subshell environment has its own rlimits (ulimit).

This has always been the case and is intended (just like cd).

This matches Austin group issue #706.

sh(1): Document new features in wait builtin.

PR: 176916

sh: Improve error handling in read builtin:

* If read -t times out, return status as if interrupted by SIGALRM
(formerly 1).
* If a trapped signal interrupts read, return status 128+sig (formerly 1).
* If [EINTR] occurs but there is no trap, retry the read (for example
because of a SIGWINCH in interactive mode).
* If a read error occurs, write an error message and return status 2.

As before, a variable assignment error returns 2 and discards the remaining
data read.

Document a few expansions for the $PS1 and $PS2 environmental variables.

PR: 173410
Submitted by: Derek Wood <ddwood@outlook.com>
Reviewed by: jilles

Minor mdoc fix.

sh(1): Mention possible ambiguities with $(( and ((.

In some other shells, things like $((a);(b)) are command substitutions.

Also, there are shells that have an extension ((ARITH)) that evaluates an
arithmetic expression and returns status 1 if the result is zero, 0
otherwise. This extension may lead to ambiguity with two subshells starting
in sequence.

Add FILES section.

Discussed with: jilles

Change the $ENV example to use .shrc instead of .shinit. This is consistent
with what we use in /usr/share/skel/dot.profile.

Discussed with: jilles

sh: Simplify cd-hash interaction.

Instead of rechecking relative paths for all hashed utilities after a cd,
track if any utility in cmdtable depends on a relative path in PATH.
If there is such a utility, cd clears the entire table.

As a result, the '*' in hash no longer happens.

mdoc: don't nest displays. The markup here isn't adding anything anyway.
Fixes a mandoc lint warning.

Discussed with: brueffer, Jason McIntyre <jmc@kerhand.co.uk>

Minor mdoc fix.

sh: Expand assignment-like words specially for export/readonly/local.

Examples:
export x=~
now expands the tilde
local y=$1
is now safe, even if $1 contains IFS characters or metacharacters.

For a word to "look like an assignment", it must start with a name followed
by an equals sign, none of which may be quoted.

The special treatment applies when the first word (potentially after
"command") is "export", "readonly" or "local". There may be quoting
characters but no expansions. If "local" is overridden with a function there
is no special treatment ("export" and "readonly" cannot be overridden with a
function).

If things like
local arr=(1 2 3)
are ever allowed in the future, they cannot call a "local" function. This
would either be a run-time error or it would call the builtin.

This matches Austin Group bug #351, planned for the next issue of POSIX.1.

PR: bin/166771

Minor mdoc nits.

mdoc: fix column names, indentation, column separation within each row, and
quotation. Also make sure we have the same amount of columns in each row as
the number of columns we specify in the head arguments.

Reviewed by: brueffer

Remove trailing whitespace per mdoc lint warning

Disussed with: gavin
No objection from: doc
Approved by: joel
MFC after: 3 days

Remove superfluous paragraph macro.

sh(1): Improve documentation of field splitting.

sh(1): Extend documentation about subshells.

Because sh executes commands in subshell environments without forking in
more and more cases (particularly from 8.0 on), it makes sense to describe
subshell environments more precisely using ideas from POSIX, together with
some FreeBSD-specific items.

In particular, the hash and times builtins may not behave as if their state
is copied for a subshell environment while leaving the parent shell
environment unchanged.

sh(1): Improve documentation of shell patterns:

* Shell patterns are also for ${var#pat} and the like.
* An '!' by itself will not trigger pathname generation so do not call it a
meta-character, even though it has a special meaning directly after an
'['.
* Character ranges are locale-dependent.
* A '^' will complement a character class like '!' but is non-standard.

MFC after: 1 week

sh(1): Document the case command better.

Suggested by: netchild
Reviewed by: gjb

sh: Add do-nothing -h option.

POSIX requires a -h option to sh and set, to locate and remember utilities
invoked by functions as they are defined. Given that this
locate-and-remember process is optional elsewhere, it seems safe enough to
make this option do nothing.

POSIX does not specify a long name for this option. Follow ksh in calling it
"trackall".

sh: Add case statement fallthrough (with ';&' instead of ';;').

Replacing ;; with the new control operator ;& will cause the next list to be
executed as well without checking its pattern, continuing until a list ends
with ;; or until the end of the case statement. This is like omitting
"break" in a C "switch" statement.

The sequence ;& was formerly invalid.

This feature is proposed for the next POSIX issue in Austin Group issue
#449.

sh: Add support for named character classes in bracket expressions.

Example:
case x in [[:alpha:]]) echo yes ;; esac

sh: Save/restore changed variables in optimized command substitution.

In optimized command substitution, save and restore any variables changed by
expansions (${var=value} and $((var=assigned))), instead of trying to
determine if an expansion may cause such changes.

If $! is referenced in optimized command substitution, do not cause jobs to
be remembered longer.

This fixes $(jobs $!) again, simplifies the man page and shortens the code.

sh: Do parameter expansion on ENV before using it.

This is required by POSIX, and allows things like ENV=\$HOME/.shrc.

Note that tilde expansion is explicitly not performed.

sh: Do parameter expansion before printing PS4 (set -x).

The function name expandstr() and the general idea of doing this kind of
expansion by treating the text as a here document without end marker is from
dash.

All variants of parameter expansion and arithmetic expansion also work (the
latter is not required by POSIX but it does not take extra code and many
other shells also allow it).

Command substitution is prevented because I think it causes too much code to
be re-entered (for example creating an unbounded recursion of trace lines).

Unfortunately, our LINENO is somewhat crude, otherwise PS4='$LINENO+ ' would
be quite useful.

sh: Expand aliases after assignments and redirections.

sh: Implement the cd -e flag proposed for the next POSIX issue.

This reflects failure to determine the pathname of the new directory in the
exit status (1). Normally, cd returns successfully if it did chdir() and the
call was successful.

In POSIX, -e only has meaning with -P; because our -L is not entirely
compliant and may fall back to -P mode, -e has some effect with -L as well.

sh: Add \u/\U support (in $'...') for UTF-8.

Because we have no iconv in base, support for other charsets is not
possible.

Note that \u/\U are processed using the locale that was active when the
shell started. This is necessary to avoid behaviour that depends on the
parse/execute split (for example when placing braces around an entire
script). Therefore, UTF-8 encoding is implemented manually.

sh(1): Update BUGS section for UTF-8 support.

sh: Add $'quoting' (C-style escape sequences).

A string between $' and ' may contain backslash escape sequences similar to
the ones in a C string constant (except that a single-quote must be escaped
and a double-quote need not be). Details are in the sh(1) man page.

This construct is useful to include unprintable characters, tabs and
newlines in strings; while this can be done with a command substitution
containing a printf command, that needs ugly workarounds if the result is to
end with a newline as command substitution removes all trailing newlines.

The construct may also be useful in future to describe unprintable
characters without needing to write those characters themselves in 'set -x',
'export -p' and the like.

The implementation attempts to comply to the proposal for the next issue of
the POSIX specification. Because this construct is not in POSIX.1-2008,
using it in scripts intended to be portable is unwise.

Matching the minimal locale support in the rest of sh, the \u and \U
sequences are currently not useful.

Exp-run done by: pav (with some other sh(1) changes)

sh(1): Describe subshell environment, command substitution more correctly.

POSIX does not require the shell to fork for a subshell environment, and we
use that possibility in various ways (command substitutions with a single
command and most subshells that are the final command of a shell process).
Therefore do not tie subshells to forking in the man page.

Command substitutions with expansions are a bit strange, causing a fork for
$(...$(($x))...) because $x might expand to y=2; they will probably be
changed later but this is how they work now.

sh(1): Reduce excessive semicolon-separated sentences.

Reported by: Benjamin Kaduk

sh(1): Update description of arithmetic.

sh: Do not try to execute binary files as scripts.

If execve() returns an [ENOEXEC] error, check if the file is binary before
trying to execute it using sh. A file is considered binary if at least one
of the first 256 bytes is '\0'.

In particular, trying to execute ELF binaries for the wrong architecture now
fails with an "Exec format error" message instead of syntax errors and
potentially strange results.

sh: Remove special code for shell scripts without magic number.

These are called "shell procedures" in the source.

If execve() failed with [ENOEXEC], the shell would reinitialize itself
and execute the program as a script. This requires a fair amount of code
which is not frequently used (most scripts have a #! magic number).
Therefore just execute a new instance of sh (_PATH_BSHELL) to run the
script.

sh(1): Document changes to 'exit' from traps.

sh(1): Explain why it is a bad idea to use aliases in scripts.

sh: Add kill builtin.

This allows specifying a %job (which is equivalent to the corresponding
process group).

Additionally, it improves reliability of kill from sh in high-load
situations and ensures "kill" finds the correct utility regardless of PATH,
as required by POSIX (unless the undocumented %builtin mechanism is used).

Side effect: fatal errors (any error other than kill(2) failure) now return
exit status 2 instead of 1. (This is consistent with other sh builtins, but
not in NetBSD.)

Code size increases about 1K on i386.

Obtained from: NetBSD

sh(1): Clean up documentation of built-in commands.

Make sure all built-in commands are in the subsection named such, except
exp, let and wordexp which are deliberately undocumented. The text said only
built-ins that really need to be a built-in were documented there but in
fact almost all of them were already documented.

sh(1): Document that command's -p option also works with -v/-V.

This was implemented in r201343.

sh: Add printf builtin.

This was removed in 2001 but I think it is appropriate to add it back:
* I do not want to encourage people to write fragile and non-portable echo
commands by making printf much slower than echo.
* Recent versions of Autoconf use it a lot.
* Almost no software still wants to support systems that do not have
printf(1) at all.
* In many other shells printf is already a builtin.

Side effect: printf is now always the builtin version (which behaves
identically to /usr/bin/printf) and cannot be overridden via PATH (except
via the undocumented %builtin mechanism).

Code size increases about 5K on i386. Embedded folks might want to replace
/usr/bin/printf with a hard link to /usr/bin/alias.

sh(1): Document r214304 (special builtin is illegal function name).

sh(1): Update for r214492. "${v+"hi}there"}".

The part hi}there is not a quoted string but nevertheless the closing brace
does not terminate the expansion.

sh(1): Modernize the introduction a bit.

In particular, remove the text about ksh-like features, which are usually
taken for granted nowadays. The original Bourne shell is fading away and for
most users our /bin/sh is one of the most minimalistic they know.

sh(1): Correct synopsis and make precise how $0 is set.

In particular, the extra argument to set $0 with -c was not documented.

MFC after: 1 week

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

sh(1): Clarify subshells/processes for pipelines.

For multi-command pipelines,
1. all commands are direct children of the shell (unlike the original
Bourne shell)
2. all commands are executed in a subshell (unlike the real Korn shell)

MFC after: 1 week

sh(1): Remove xrefs for expr(1) and getopt(1).

expr(1) should usually not be used as various forms of parameter expansion
and arithmetic expansion replicate most of its functionality in an easier
way.

getopt(1) should not be used at all in new code. Instead, getopts(1) or
entirely manual parsing should be used.

MFC after: 1 week

sh(1): Add a brief summary of arithmetic expressions.

sh: Forget about terminated background processes sooner.

Unless $! has been referenced for a particular job or $! still contains that
job's pid, forget about it after it has terminated. If $! has been
referenced, remember the job until the wait builtin has reported its
completion (either with the pid as parameter or without parameters).

In interactive mode, jobs are forgotten after termination has been reported,
which happens before primary prompts and through the jobs builtin. Even
then, though, remember a job if $! has been referenced.

This is similar to what is suggested by POSIX and should fix most memory
leaks (which also tend to cause sh to use more CPU time) with long running
scripts that start background jobs.

Caveats:
* Repeatedly referencing $! without ever doing 'wait', like
while :; do foo & echo started foo: $!; sleep 60; done
will still use a lot of memory and CPU time in the long run.
* The jobs and jobid builtins do not cause a job to be remembered for longer
like expanding $! does.

PR: bin/55346

sh(1): Rework documentation of shell variables.

* Move the "environment variables" that do not need exporting to be
effective or that are set by the shell without exporting to a new section
"Special Variables".
* Add special variables LINENO and PPID.
* Add environment variables LANG, LC_* and PWD; also describe ENV under
environment variables.

sh(1): Improve wording of 'Special Parameters' section.

sh(1): Fix "reserved word" vs "keyword" inconsistency.
Use "keyword" everywhere, like the output of the 'type' builtin, and only
mention "reserved word" once to say it is the same thing.

MFC r197848: Clarify quoting of word in ${v=word} in sh(1).

sh: Automatically enable -o emacs in interactive shells with terminals.

This makes sh a bit more friendly in single user mode, make buildenv, chroot
and the like, and matches other shells.

The -o emacs can be overridden on the command line or in the ENV file.

sh: Document the expansion changes in the man page.

Note that the following sentence
> Enclosing the full parameter expansion string in double-quotes does not
> cause the following four varieties of pattern characters to be quoted,
> whereas quoting characters within the braces has this effect.
is now true, but used to be incorrect.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

sh: Improve the command builtin:
* avoid unnecessary fork
* allow executing builtins via command
* executing a special builtin via command removes its special properties

Obtained from: NetBSD (parts)

MFC r201355: sh(1): document ulimit -w (swapuse rlimit).

MFC r201354: sh(1): Correct two places where "$@" lacked necessary quotes.

sh(1): document ulimit -w (swapuse rlimit).

MFC after: 1 week

sh(1): Correct two places where "$@" lacked necessary quotes.

MFC after: 1 week

MFC r197371: Mention that NUL characters are not allowed in sh(1) input.

I do not consider this a bug because POSIX permits it and argument strings
and environment variables cannot contain '\0' anyway.

PR: bin/25542

sh: Exempt $@ and $* from set -u

This seems more useful and will likely be in the next POSIX standard.

Also document more precisely in the man page what set -u does (note that
$@, $* and $! are the only special parameters that can ever be unset, all
the others are always set, although they may be empty).

Clarify quoting of word in ${v=word} in sh(1).

Mention that NUL characters are not allowed in sh(1) input.

I do not consider this a bug because POSIX permits it and argument strings
and environment variables cannot contain '\0' anyway.

PR: bin/25542
MFC after: 2 weeks

Designate special builtins as such in command -V and type.
Also document various properties of special builtins that we implement.

Approved by: ed (mentor) (implicit)

Mention the range for the exit status for the exit special builtin.

The exit status may exceed 255 in some cases (return); even though it seems
unwise to rely on this, it is also unwise to assume that $? is always
between 0 and 255.

This resolves bin/124748 by documenting that 'exit -1' is not valid.

PR: bin/124748
Approved by: ed (mentor)

sh: Make read's timeout (-t) apply to the entire line, not only the first
character.

This avoids using non-standard behaviour of the old (upto FreeBSD 7) TTY
layer: it reprocesses the input queue when switching to canonical mode. The
new TTY layer does not provide this functionality and so read -t worked
very poorly (first character is not echoed, cannot be backspaced but is
still read).

This also agrees with what most other shells with read -t do.

PR: bin/129566
Reviewed by: stefanf
Approved by: ed (mentor)

- Import the HEAD csup code which is the basis for the cvsmode work.

Document the ulimit -p option in the sh(1) manual page.

When I imported the MPSAFE TTY code, I added the -p flag to sh(1)'s
ulimit, but I forgot to document it in the appropriate manual page.

Requested by: stefanf

Revise the markup.

The exit status of a case statement where none of the patterns is matched
is supposed to be 0, not the status of the previous command.

Reported by: Eygene Ryabinkin
PR: 116559
Approved by: re (gnn)

Add the POSIX option -p to the jobs builtin command. It prints the PID of the
process leader for each job. Now the last specified option for the output
format (-l, -p or -s) wins, previously -s trumped -l.

PR: 99926
Submitted by: Ed Schouten and novel (patches modified by me)

Markup fixes.

Tell more of the sh(1) history.
Acknowledge Kenneth Almquist's contribution in AUTHORS.

MFC after: 5 days

Make it easier to find that we have test(1) built-in in sh(1).

MFC after: 3 days

Document the fact that 'true' and 'false' are among sh(1) built-in commands.

MFC after: 3 days

Implement the PS4 variable which is defined by the POSIX User Portability
Utilities option. Its value is printed at the beginning of the line if tracing
(-x) is active. PS4 defaults to the string "+ " which is compatible with the
old behaviour to always print "+ ".

We still need to expand variables in PS1, PS2 and PS4.

PR: 46441 (part of)
Submitted by: schweikh
Obtained from: NetBSD

Document that '#' starts a comment.

PR: 85103
Submitted by: garys
Obtained from: pdksh manual
Patch from: Daniel Gerzo (with changes by me)

- Document trap's -l option and the behaviour of a missing action or a single
dash.
- Discourage the omission of the action.

PR: 70985 [1]
Submitted by: Martin Kammerhofer

Clarify that the echo builtin takes an arbitrary number of strings.
Mention that spaces are printed between the strings.

Add the times builtin. It reports the user and system time for the shell
itself and its children. Instead of calling times() (as implied by POSIX) this
implementation directly calls getrusage() to get the times because this is more
convenient.

-mdoc sweep.

Add `local' and `return' to the list of built-ins.

Submitted by: garys
Approved by: trhodes (mentor)

Document command -v and -V.

Glanced at by: simon

Document that read -t timeout returns 1 if the timeout elapses.

Elaborate on the behaviour of set -e.

Split the export synopsis into two lines as -p cannot be mixed with variable
names.

fix typo: ommitted -> omitted

Document that `in word ...' is optional in the for command.

Document that unalias can be used to remove several alias names.

Wrap a line due to a new sentence.

Noticed by: simon
Approved by: trhodes (mentor)

o Discuss the ways to escape an alias.
o Fix the alias syntax lines.
o Refer to the Aliases subsection.

PR: docs/84914
Submitted by: garys
Approved by: trhodes (mentor)
MFC after: 3 days

Document umask's -S option.

Sorted sections and fixed prompt (PS[12]) strings.

Approved by: re (blanket)

Put the description of the -c option in the right place, as
promised by the Argument List Processing section introduction.
What follows the option in the options list is its long name,
not its argument (as is the case for the -c option). Also
sort references in the SEE ALSO section.

Approved by: re (blanket)

Various sh(1) enhancements:
- Move the description of the ``-c string'' option closer to the option itself.
- Add an ENVIRONMENT section (1)
- Add more .Xr cross references to the SEE ALSO section.

Obtained from: NetBSD (1)

Use ``.Pq Ql'' to quote single characters, instead of ``.Pq Li''.
This makes the resulting output more aesthetically pleasing in
text-only terminals:

Reviewed by: ru

Add a section describing the exit status of the shell.

Obtained from: NetBSD

/*- or .\"- or #- to begin license clauses.

Scheduled mdoc(7) sweep.

Correct typo.

o Add a missed "." .

Reviewed by: ru
MFC after: 3 weeks

When listing the special $ variables, ($!, $#, etc) list them as $!
instead of just !, this allows one to more easily locate/understand
the section of the manpage in question.

Additional wording correction by: keramida
Reviewed by: keramida

Document missing multibyte character handling in utilities specified
by POSIX.

Mechanically kill hard sentence breaks.

Document the "return" built-in better: it will exit . (sources) and
the top-level shell instance, too.

Remove clause 3 from the UCB licenses.

OK'ed by: imp, core

mdoc(7): Use the new feature of the .In macro.

mdoc(7) police: A better version of the same.

Approved by: re (blanket)

Fix references to non-existing or obsoleted man pages.

PR: docs/51480 (only a small part)
Submitted by: Diomidis D. Spinellis <dds@aueb.gr>

Document the -L and -P options to the cd and pwd commands as being
mutually exclusive. The fact that the most recent one specified on the
command line is the one that takes effect is an implementation detail and
users should not rely on this.

Improve the layout of the description of the various parameter expansion
modifiers. The paragraph that explains the difference between ${foo:-bar}
and ${foo-bar} etc. was not very visible.

mdoc(7) police: Deal with self-xrefs.

mdoc(7) police: markup nit.

The code uses trapsasync, however the manual page uses asynctraps. Fix the
manual page to reflect the code.

PR: 45820
Submitted by: Marco Molteni <molter@tin.it>
Discussed with: tjr

Document `trap EXIT` and `trap SIGNAME`.

There is a built-in command called "builtin"; spell its name correctly
after rev. 1.77 called it "built-in".

s/filesystem/file system/ as discussed on -developers

Fix a few typos, among them s/builtin/built-in/ (except for the ref
to the builtin(1) man page.) This is for consistency with the spelling
both proposed by ispell as well as IEEE Std 1003.1-2001.

MFC after: 3 days

mdoc(7) police: tidying.

Add a -P/-o physical option which behaves similarly to bash/ksh's options
by the same name. This option makes the cd and pwd builtins behave physically
(as opposed to logically) by default.

Submitted by: fanf

Add a `bind' builtin command, which is simply a wrapper around libedit's
builtin command of the same name. This allows the key bindings for the
shell's line editor to be changed.

MFC after: 2 weeks

Implement the P1003.2 `command' builtin command, which is used to suppress
shell function and alias lookup. The -p option has been implemented, the
UPE -v and -V options have not. The old `command' command has been renamed
to `builtin'.

Document that only one of the -n and -e options may be specified for
sh(1)'s echo(1) builtin command.

PR: 32935, 40747
MFC after: 1 week

Fix type-o in last commit in preparation for MFC.

Document addition of RLIMIT_VMEM support, added in rev 1.26 of miscbltin.c.

Bring documentation on CDPATH and its effects on cd(1) back into sync with
reality (and POSIX): current directory isn't searched unless CDPATH has
a "." element or is unset.

PR: 38442
Submitted by: oleg dashevskii <be9@be9.ru>
MFC after: 1 week

Document the -f and -v options of the unset builtin.

Add the SUSv3 -p ("portable") option to both the export and readonly
builtins. This makes export/readonly print lines in the form
"export name=value".

Quote alias values in the output of the alias(1) builtin so they are
suitable for re-input to the shell (SUSv3)

Add -s (output PID's only) and -l (show PID's) options to the jobs(1)
builtin. Modify the output format to match what SUSv3 requires.

mdoc(7) police: tidy up the markup a bit.

sh appeared in Version 1, not System V.1.

Implement `set +o', which displays the currently set options in a format
suitable for re-input into the shell.

Add the SUSv3 -L and -P options to the cd and pwd builtin utilities. `Logical'
handling of .. is now the default.

Implement the -u (-o nounset) option, which gives an error message if
an unset variable is expanded.

Obtained from: NetBSD (bjh21, christos)

Implement the -C (-o noclobber) option, which prevents existing regular
files from being overwritten by shell redirection.

Remove the printf builtin command from sh(1), which command is not
used so often that it's worth keeping it as a builtin.

Now that all the printf invocations from within the system startup
scripts, we can safely remove it.

Urged by: sheldonh :)

No MFC is planned so far because it may break compatibility and
violate POLA.

Make test(1) a builtin command of our sh(1) for efficiency. The
binary size increase is 3,784 bytes (about 0.6%).

I don't drop the printf builtin while I'm here because some /etc/rc.*
scripts seem to use it before mounting /usr where printf(1) resides.

Reviewed by: arch (sheldonh)
Inspired by: NetBSD, ksh
Clued by: ume (on how the printf builtin is used)

can not -> cannot

mdoc(7) police:

Avoid using parenthesis enclosure macros (.Pq and .Po/.Pc) with plain text.
Not only this slows down the mdoc(7) processing significantly, but it also
has an undesired (in this case) effect of disabling hyphenation within the
entire enclosed block.

Break the list of parameter expansions into two lists so that
the paragraph introducing the prefix and suffix pattern expansions
does not appear as part of the explanation for the string length
expansion.

mdoc(7) police: removed HISTORY info from the .Os call.

mdoc(7) police: sort SEE ALSO xrefs (sort -b -f +2 -3 +1 -2).

Remove duplicate words.

Document "chdir" builtin.

mdoc(7) police: split punctuation characters + misc fixes.

Prepare for mdoc(7)NG.

Prepare for mdoc(7)NG.

Prepare for mdoc(7)NG.

mdoc(7) police: Er macro usage cleanup.

Implement the <> redirection operator.

Mark up the -a flag to unalias as a flag (Fl), not an argument (Ar).

Add missing punctuation to one line.

Document the builtin echo command

Reviewed by: Matthew Hunt <mph@astro.caltech.edu>

Document ulimit -b for RLIMIT_SBSIZE.

make '|' character visible.

PR: docs/15265
Submitted by: takamune@avrl.mei.co.jp

Follow-up on mdoc fixes in rev 1.35; this includes things that I missed
in that revision as well as things I broke in that revision. A note-
worthy instance of the latter case was the inversion of -E and -V in the
subsection on Commandline Editing.

Don't call bash(1) a Korn shell clone. Instead, use pdksh(1) as an
example of such a clone.

PR: 14601
Submitted by: Matthias Buelow <mkb@altair.mayn.de>

Mdoc cleanup, with a few grammar cleanups on the side.

Reviewed by: mpp

Correct some hard sentence breaks. Only those surrounding the previous
commit and those which cause ugly nroff output have been fixed, since
the purpose of the style guideline which they contravene is to reduce
the sizes of deltas.

Reported by: bde

Improve shell documentation:

* Consistently misspell built-in as builtin.

* Add a builtin(1) manpage and create builtin(1) MLINKS for all shell
builtin commands for which no standalone utility exists. These MLINKS
replace those that were created for csh(1).

* Add appropriate xrefs for builtin(1) to the csh(1) and sh(1) manpages,
as well as to the manpages of standalone utilities which are supported
as shell builtin commands in at least one of the shells. In such
manpages, explain that similar functionality may be provided as a
shell builtin command.

* Improve sh(1)'s description of the cd builtin command. Csh(1) already
describes it adequately. Replace the cd(1) manpage with a builtin(1)
MLINKS link.

* Clean up some mdoc problems: use Xr instead of literal "foo(n)"; use
Ic instead of Xr for shell builtin commands.

* Undo English contractions.

Reviewed by: mpp, rgrimes

Revert to using .Xr for builtins. The cross-references don't work now,
but that doesn't mean that they will never work.

Requested by: mpp, rgrimes

Clean-up:

Fix grammar and spelling nits.
Use .Dq and .Qq where appropriate.
Divorce trailing punctuation from quoted elements.
Use .Dq instead of .Xr for builtins.
Remove trailing whitespace and blank lines.

PR: 13340

$Id$ -> $FreeBSD$

Make the behaviour of `read -e', ie. treating backslashes as special,
the default. Add -r option for the read builtin to reverse this.

PR: 13274
Reviewed by: cpiazza, hoek, sheldonh

Typo fix.

Implement -a flag. A test shell script can be found at
http://www.cons.org/cracauer/download/sh-interrupt/testsuite/test_export.sh
The PR also had test cases the new version passes.

Fix typo in comment.

PR: bin/1030

-T was missing in the synopsis line.

Submitted by: BDE

The immediate execution of traps I introduced in September 1998 (to
make /etc/rc interruptible in cases when programs hang with blocked
signals) isn't standard enough.

It is now switched off by default and a new switch -T enables it.

You should update /etc/rc to the version I'm about to commit in a few
minutes to keep it interruptible.

sh doesn't support <> redirections.
PR: 7325

Add references to test(1) and expr(1).

Fix typo. "If the an entry" --> "If an entry"

PR: docs/8140
Submitted by: Sue Blake <sue@vedanix.welearn.com.au>

Document behaviour of "-" and "--" on the command line.

PR: docs/5399

Add rcsid. Spelling.

Explicitly describe the rules the shell uses to search for a file
sourced by the "." command.

Correct a bogon in an example.

PR: 5415
Submitted by: Sergei S. Laskavy <laskavy@pc759.cs.msu.su>

Document the exit status for a command that was terminated by a
signal.

Add the '-t timeout' option to the 'read' builtin. This allows the
'read' command to return an error if the user fails to supply any
input withink a given time period. The behaviour of this option is
similar to that of the like-named option in ksh93.

Reviewed by: joerg

PR: docs/4449
The -c flag is not documented in the sh(1) manapge.

Submitted by: adrian@virginia.edu

Revise the section that explains how to protect parts of an $ENV script
from being executed in non-interactive mode.

Suggested and Reviewed by: Brian Somers <brian@freebsd.org>

mdoc-ify and cleanup UNIMPLEMENTED messages. Closes PR 2880.

Revert $FreeBSD$ to $Id$

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Merge in NetBSD mods and -Wall cleaning.

Obtained from: NetBSD, me

Add the -p (privileged) commandline switch
found in bash, zsh, and friends.

Reviewed by: joerg

Fix for PR#1287. This makes sh behave sensibly in case statements in the
face of aliases. Note, bash doesn't do aliases while running scripts, but
"real" ksh does..

Also:
Reduce redundant .Nm macros in (unused) bltin/echo.1
nuke error2, it's hardly used.
More -Wall cleanups
dont do certain history operations if NO_HISTORY defined
handle quad_t's from resource limits

Submitted by: Steve Price <sprice@hiwaay.net> (minor tweaks by me)

Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault... mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do. The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter

[HISTORY] command appeared in Version 1 AT&T UNIX
Obtained from: A Quarter Century of UNIX, Peter H. Salus, page 41

Import the 4.4BSD-Lite2 /bin/sh sources

Requested by: joerg

(Note, this is mostly going to be conflicts, which is expected. Our entire
sh source has a mainline, so this should not change anything except for
a few new files appearing. I dont think they are a problem)

o rename ulimit -p into ulimit -u, so we are in agreement with bash

o fix brokeness for 1>&5 redirection, where `5' was an invalid file
descriptor, but no error message has been generated

o fix brokeness for redirect to/from myself case

Implement the "ulimit" builtin. This is the analogon to csh's "limit"
command and badly needed in sh(1) for everybody who wants to modify
the system-wide limits from inside /etc/rc.

The options are similar to other system's implemantations of this
command, with the FreeBSD additions for -m (memoryuse) and -p (max
processes) that are not available on other systems.

typo there --> their

Added $Id$

BSD 4.4 Lite bin Sources