(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