Examples:
LC_ALL=en_US.UTF-8 printf '%d\n' $(printf \'\\303\\244)
LC_ALL=en_US.ISO8859-1 printf '%d\n' $(printf \'\\344)
Both of these should print 228.
Like some other shells, incomplete or invalid multibyte characters yield the
value of the first byte without a warning.
Note that there is no general way to go back from the character code to the
character.
CDPATH should be ignored not only for pathnames starting with '/' but also
for pathnames whose first component is '.' or '..'.
The man page already describes this behaviour.
If IFS is null, unquoted $@/$* should still expand to separate words.
This differs from quoted $@ (which does not depend on IFS) in that pathname
generation is performed and empty words are removed.
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.
This is sometimes used with eval or old-style command substitution, and most
shells other than ash derivatives allow it.
It can also be used with scripts that violate POSIX's requirement on the
application that they end in a newline (scripts must be text files except
that line length is unlimited).
Example:
v=`cat <<EOF
foo
EOF`
echo $v
This commit does not add support for the similar construct with new-style
command substitution, like
v=$(cat <<EOF
foo
EOF)
This continues to require a newline after the terminator.
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.
?, [...] patterns match codepoints instead of bytes. They do not match
invalid sequences. [...] patterns must not contain invalid sequences
otherwise they will not match anything. This is so that ${var#?} removes the
first codepoint, not the first byte, without putting UTF-8 knowledge into
the ${var#pattern} code. However, * continues to match any string and an
invalid sequence matches an identical invalid sequence. (This differs from
fnmatch(3).)
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)
Note that this only applies to variables that are actually used.
Things like (0 && unsetvar) do not cause an error.
Exp-run done by: pav (with some other sh(1) changes)
In particular, this makes things like ${#foo[0]} and ${#foo[@]} errors
rather than silent equivalents of ${#foo}.
PR: bin/151720
Submitted by: Mark Johnston
Exp-run done by: pav (with some other sh(1) changes)
Ensure that system calls that access global namespaces, e.g. open(2), are not permitted, and that whitelisted sysctls like kern.osreldate are.
Approved by: rwatson
Sponsored by: Google, Inc.
For backgrounded pipelines and subshells, the previous value of $? was being
preserved, which is incorrect.
For backgrounded simple commands containing a command substitution, the
status of the last command substitution was returned instead of 0.
If fork() fails, this is an error.
If EV_EXIT causes an exit, use the exception mechanism to unwind
redirections and local variables. This way, if the final command is a
redirected command, an EXIT trap now executes without the redirections.
Because of these changes, EV_EXIT can now be inherited by the body of a
function, so do so. This means that a function no longer prevents a fork
before an exec being skipped, such as in
f() { head -1 /etc/passwd; }; echo $(f)
Wrapping a single builtin in a function may still cause an otherwise
unnecessary fork with command substitution, however.
An exit command or -e failure still invokes the EXIT trap with the
original redirections and local variables in place.
Note: this depends on SHELLPROC being gone. A SHELLPROC depended on
keeping the redirections and local variables and only cleaning up the
state to restore them.
- Test newslog with clasic naming of rotates files to actually test
the correct number of log files as newsyslog now does the correct
thing post r220926.
- Add some more newsyslog tests which tests keeping 0, 1, and 2
logfiles.
This is only a problem if IFS contains digits, which is unusual but valid.
Because of an incorrect fix for PR bin/12137, "${#parameter}" was treated
as ${#parameter}. The underlying problem was that "${#parameter}"
erroneously added CTLESC bytes before determining the length. This
was properly fixed for PR bin/56147 but the incorrect fix was not backed
out.
Reported by: Seeker on forums.freebsd.org
MFC after: 2 weeks
Of course, strerror_r() may still fail with ERANGE.
Although the POSIX specification said this could fail with EINVAL and
doing this likely indicates invalid use of errno, most other
implementations permitted it, various POSIX testsuites require it to
work (matching the older sys_errlist array) and apparently some
applications depend on it.
PR: standards/151316
MFC after: 1 week
These already worked: $# ${#} ${##} ${#-} ${#?}
These now work as well: ${#+word} ${#-word} ${##word} ${#%word}
There is an ambiguity in the standard with ${#?}: it could be the length of
$? or it could be $# giving an error in the (impossible) case that it is not
set. We continue to use the former interpretation as it seems more useful.
The test was support to check if SUID/SGID bits are removed on first
write, but actually we were checking if they were removed after close.
Now we can check if SUID/SGID bits are gone after first write.
While here add checks to see if when both SUID and SGID bits are set they are
both cleared on first write.
- fchmod(2),
- fchown(2),
- fchflags(2),
- fstat(2),
- ftruncate(2),
- fpathconf(2),
- lpathconf(2).
Make write(2) syscall to take descriptor instead of file name.
We implement descriptors by keeping track of open files and allowing to
reference them by the following syscalls. Because pjdfstest already supports
executing multiple syscalls from one command it works pretty well.
For example, the following command:
pjdfstest open foo "O_CREAT,O_RDWR" 0 : open bar "O_CREAT,O_RDONLY" 640 : fchmod 0 0666 : fchown 0 -1 20 : fchmod 1 0444
is equivalent of (error checking omitted):
int fd[2];
fd[0] = open("foo", O_CREAT | O_RDWR, 0);
fd[1] = open("bar", O_CREAT | O_RDONLY, 0640);
fchmod(fd[0], 0666);
fchown(fd[0], -1, 20);
fchmod(fd[1], 0444);
Preserving $? may cause problems particularly if set -e is in effect.
It may be useful to preserve the old value of $? in the dot script but this
must not be implemented in such a way that it would break this test.
