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).
the line number where the command substitution started.
This applies to both the $() and `` forms but is most useful for ``
because the other line number is relative to the enclosed text there.
(For older versions, -v can be used as a workaround.)
According to the man page, when neither -H/-L nor -F/-d/-l are given, -H is
implied. This agrees with POSIX, GNU ls and Solaris ls. This means that -p,
although it is very similar to -F, does not prevent the implicit following
of symlinks.
PR: standards/128546
This also fixes that trying to execute a non-regular file with a command
name without '/' returns 127 instead of 126.
The fix is rather simplistic: treat CMDUNKNOWN as if the command were found
as an external program. The resulting fork is a bit wasteful but executing
unknown commands should not be very frequent.
PR: bin/137659
Due to the amount of code removed by this, it seems that allowing unmatched
quotes was a deliberate imitation of System V sh and real ksh. Most other
shells do not allow unmatched quotes (e.g. bash, zsh, pdksh, NetBSD /bin/sh,
dash).
PR: bin/137657
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
Note that this changes error reporting behaviour somewhat - before,
no error was reported if ACL couldn't be copied because the target
filesystem doesn't support ACLs. Now, it will be reported - of course,
only if there actually is an ACL to copy.
Reviewed by: rwatson
- Keep variables sorted
- Fix logic error with -f and -v options - don't print
the usual -v output if there was an error, whether or not
we were passed -f
- Don't call free(3) just before exit(2)
- Whitespace fixes
Submitted by: bde
Empty pairs of braces are represented by a NULL node pointer, just like
empty lines at the top level.
Support for empty pairs of braces may be removed later. They make the code
more complex, have inconsistent behaviour (may or may not change $?), are
not specified by POSIX and are not allowed by some other shells like bash,
dash and ksh93.
Reported by: kan
Add a reference count to function definitions.
Memory may leak if multiple SIGINTs arrive in interactive mode,
this will be fixed later by changing SIGINT handling.
PR: bin/137640
This implements the POSIX.1-2008 -L and -P flags.
The default remains to create hard links to the target of symlinks.
Approved by: re (kib), ed (mentor)
is identical to the mode computed from that ACL will modify the ACL.
For example, mode computed from the following ACL is 0600:
user:kamila:rwx--------C--:------:allow
owner@:--x-----------:------:deny
owner@:rw-p---A-W-Co-:------:allow
group@:rwxp----------:------:deny
group@:--------------:------:allow
everyone@:rwxp---A-W-Co-:------:deny
everyone@:------a-R-c--s:------:allow
However, applying that mode (chmod 0600) changes the ACL into this:
user:kamila:rwx-----------:------:deny
user:kamila:rwx--------C--:------:allow
owner@:--x-----------:------:deny
owner@:rw-p---A-W-Co-:------:allow
group@:rwxp----------:------:deny
group@:--------------:------:allow
everyone@:rwxp---A-W-Co-:------:deny
everyone@:------a-R-c--s:------:allow
In chmod(1) utility, there is an optimisation, which makes it not
call chmod(2) if the mode of the file is the same as the new mode.
Disable that optimisation for files which may have NFSv4 ACLs.
Reviewed by: rwatson
Approved by: re (kib)
in particular "$@"$ifschar if the final positional parameter is empty.
With the NetBSD code, adding the $ifschar removes a parameter.
PR: standards/79067
Approved by: ed (mentor) (implicit)
(EV_EXIT). The fork is still done as normal if any traps are active.
In many cases, the fork can be avoided even without this change by using {}
instead of (), but in practice many scripts use (), likely because the
syntax is simpler.
Example:
sh -c '(/bin/sleep 10)& sleep 1;ps -p $! -o comm='
Now prints "sleep" instead of "sh". $! is more useful this way.
Most shells (dash, bash, pdksh, ksh93, zsh) seem to print "sleep" for this.
Example:
sh -c '( ( ( (ps jT))))'
Now shows no waiting shell processes instead of four.
Most shells (dash, bash, pdksh, ksh93, zsh) seem to show zero or one.
PR: bin/74404
Approved by: ed (mentor) (implicit)
- update for getrlimit(2) manpage;
- support for setting RLIMIT_SWAP in login class;
- addition to the limits(1) and sh and csh limit-setting builtins;
- tuning(7) documentation on the sysctls controlling overcommit.
In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)
- remove ineffective and unnecessary (void) &var; [1]
- remove some unnecessary volatile keywords
- add a necessary volatile keyword
- save the old handler before doing something that could use the saved
value
Submitted by: Christoph Mallon [1]
Approved by: ed (mentor)
Formerly, it was possible for the file to be created between the check if it
existed and the open; the contents would then be lost.
Because this must use O_EXCL, noclobber > will not create a file through a
symlink anymore. This agrees with behaviour of other shells.
Approved by: ed (mentor) (implicit)
Output quoted suitable for re-input to the shell occurs in
various cases such as 'set', 'trap'.
Bugfix: *, ? and [ must be quoted (except sole [)
Bugfix: ~ and # must be quoted (really only sometimes, but keep it simple)
Bugfix: space, tab and newline must always be quoted
Shortening: other IFS characters do not need quoting
Bugfix: send to correct output file, not hard-coded stdout
Shortening: avoid unnecessary '' with \'
Approved by: ed (mentor)
For parsing an old-style backquote substitution (`...`),
a string "file" is used to store the contents of the
substitution (with the special backslash processing done).
If an error occurs, the shell cleans up all these files
(returning to the top level) and flush the top level
file. Erroneously, it first flushed the current file and
then cleaned up all extra files, so that the top level
file (i.e. the terminal) was not flushed.
Example (in interactive mode):
echo `for` echo This should not be printed
Also noticeable in (in interactive mode):
echo `(`
The old version prints an extraneous prompt.
Approved by: ed (mentor)
This change only affects strings passed to -c, when the -s
option is not used.
The approach is to check if there may be additional data
in the string after parsing each command. If there is none,
use the EV_EXIT flag so that a fork may be omitted in
specific cases.
If there are empty lines after the command, the check will
not see the end and forks will not be omitted. The same
thing seems to happen in bash.
Example:
sh -c 'ps lT'
No longer shows a shell process waiting for ps to finish.
PR: bin/113860
Reviewed by: stefanf
Approved by: ed (mentor)
Example:
sh -c '(trap "echo trapped" EXIT; sleep 3)'
now correctly prints "trapped".
With this check, it is no longer necessary to check for -T
explicitly in that case.
This is a useful bugfix by itself and also important because I plan to
skip forking more often.
PR: bin/113860 (part of)
PR: bin/74404 (part of)
Reviewed by: stefanf
Approved by: ed (mentor)
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 $? is always
between 0 and 255.
This resolves bin/124748 by documenting that 'exit -1' is not valid.
PR: bin/124748
Approved by: ed (mentor)
Base 10 is always used for the inode counts as I could not think of any
reason base 2 inode counts would be useful.
Minor mdoc markup fix to df(1) while here anyway.
MFC after: 3 weeks
character.
This avoids using non-standard behaviour of the old (upto FreeBSD 7) TTY
layer: it reprocesses the input queue when switching to canonical mode. The
new TTY layer does not provide this functionality and so read -t worked
very poorly (first character is not echoed, cannot be backspaced but is
still read).
This also agrees with what most other shells with read -t do.
PR: bin/129566
Reviewed by: stefanf
Approved by: ed (mentor)
would always terminate if eval returned with a non-zero exit status regardless
if the status was actually tested. Unfortunately a new file-scope variable
is needed, the alternative would only be to add a new parameter to all
built-ins.
PR: 134881
Formerly, this tried to clear the flags on the symlink's target
instead of the symlink itself.
As before, this only happens for root or for the unlink(1) variant of rm.
PR: bin/111226 (part of)
Submitted by: Martin Kammerhofer
Approved by: ed (mentor)
MFC after: 3 weeks
More precisely, this gives precedence to an interpretation not using the
'(', ')', '-a' and '-o' in their special meaning, if possible. For example,
it is now safe to write [ "$a" = "$b" ] and assume it compares the two
strings.
The man page already says that test(1) works this way, so does not need to
be changed.
Interpretation of input with more parameters tries a bit harder to find a
valid parse in some cases.
Add various additional test cases to TEST.sh.
PR: standards/133369
Approved by: ed (mentor)
always surprising when you kill a 'sh -c ...' ancestor or when you kill
yourself when using -f.
Add a -a switch for backwards compatibility.
MFC after: 3 weeks
A difference between the old and the new TTY layer is that the new
implementation does not perform any post-processing before returning
data back to userspace when calling read().
sh(1)'s read turns the TTY into a raw mode before calling select(). This
means that the first character will not receive any ICRNL processing.
Inherit this flag from the original terminal attributes.
Even though this issue is not present on RELENG_*, I'm MFCing it to make
sh(1) in jails behave better.
PR: bin/129566
MFC after: 2 weeks
label is choosen as last printout (ucomm suffers of this such bug
too). That bug is caused by the fact that the fixed size of
printout doesn't leave enough space for them to be printed out.
Implement ucomm and comm commands with a dynamic size lenght for
buffers.
[2] On AMD64 architecture pointers don't have enough chars space to
be shown (8 chars while they need 16). Fix them by providing
a variadic space so that it fits well on both 64 and 32 bits
architectures.
[3] Check a return value of malloc() that wasn't checked before.
PR: bin/128841, bin/128842
Reviewed by: jhb, emaste
Sponsored by: Sandvine Incorporated
symlinks after setting the owner. As a result, mode
and timestamp were not restored. This patch corrects the
problem by simply removing the short-circuit for symlinks
and using lchown()/lchmod()/lutimes() always for restoring
metadata.
PR: bin/91316
Submitted by: Jaakko Heinonen
Reviewed by: Joerg Sonnenberger
MFC after: 14 days
This should be a bit useful for users who look at the manpage and
then try to copy data CD-ROM disks using dd. A lot of us know
that bs=2048 is required, but it still manages to cause a bit of
grief to those who haven't heard about it.
PR: bin/130857
Submitted by: Tri Brotoharsono < mail at tribrotoharsono.net >
MFC after: 3 days
rather than a voltag name, do not set the CESR_VOLTAGS flags in the
CHIOGSTATUS command requesting the current status. As voltags are an
optional feature that must be handled as "reserved" by media changers
not implementing the feature, always setting CESR_VOLTAGS resulted in
the command being aborted with an `Invalid field in CDB', and
consequently the "chio return" failed, for media changers that do not
support voltags.
MFC after: 1 week
in the system. A simple heuristics is used to detect what is "enough"
memory: if number of physmem pages is greater than 32k (equalling 128 MB
on machines with 4 kB pages).
Typical immediate result of these changes is reduction in context switches
and the goal is to increase efficiency by using large buffers:
before: /usr/bin/time -hlp cat file1 > file2
...
163 voluntary context switches
11194 involuntary context switches
after: /usr/bin/time -hlp ./cat file1 > file2
...
417 voluntary context switches
272 involuntary context switches
Reviewed by: hackers@ (no objections to earlier version of cat patch)
Approved by: gnn (mentor)
MFC after: 4 months
In my previous commit I disabled pkill(1)'s automatic prepending of the
"tty" string when `pkill -t' was being used. Re-enable it and stat()
both possible device names when called.
Requested by: jhb, rwatson (MFC)
MFC after: 1 month
Because we now enforce UNIX98-style PTY's, we now use a lot of TTY's
that don't have the traditional /dev/ttyXX naming scheme. pkill(1)'s -t
flag automatically prepended the word "tty" to each TTY that was passed
on the command line. This meant that `pkill -t pts/0' was actually
converted to /dev/ttypts/0. Disable this broken behaviour for now.
Reported by: erwin
Initially, 'acl' (an 'acl_t *') is allocated, and its ACCESS_ACL and
DEFAULT_ACL fields are passed to the 'libc' ACL routines for subsequent
allocation. If the '-m' option (merge existing ACL with a new one) is
specified, then 'set_acl_mask()' will be called and passed one of the
two ACLs. This function, in turn, replaces this given ACL structure by
another, freshly allocated. However, the pointer in the 'acl' variable
in the caller is not updated. The caller then proceeds to free the ACL,
incurring in a double free condition.
Submitted by: Pedro Martelletto <pedro at ambientworks.net>
Approved by: rwatson (mentor)
for the convenience of rc.d. Now it has happily lived there for quite
a while. So move the pkill(1) source files from usr.bin to bin, too.
Approved by: gad
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
After the MPSAFE TTY import, we have support for the TAB0 and TAB3 flags
to handle tab expansion, while we only used to support OXTABS. Switch
stty(1) to use tab0 and tab3 to print whether tab expansion is turned on
or off. Implement the oxtabs and tabs switches by setting the
appropriate TABx value.
Even though POSIX only lists this as being XSI, we'd better follow it.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
understand which code paths aren't possible.
This commit eliminates 117 false positive bug reports of the form
"allocate memory; error out if pointer is NULL; use pointer".