If the -p option is turned off, privileges from a setuid or setgid binary
are dropped. Make sure to check if this succeeds. If it fails, this is an
error which will cause the shell to abort except in interactive mode or if
'command' was used to make 'set' or an outer 'eval' or '.' non-special.
Note that taking advantage of this feature and writing setuid shell scripts
seems unwise.
MFC after: 1 week
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.
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.
are used to modify the arguments. Not doing so caused random memory reads or
null pointer dereferences when 'getopts' was called again later (SUSv3 says
getopts produces unspecified results in this case).
PR: 48318
demanded by POSIX.
- A redirection error is only fatal (meaning the execution of a shell script is
terminated) for special built-ins. Previously it was fatal for all shell
builtins, causing problems like the one reported in PR 88845.
- Variable assignments remain in effect for special built-ins.
- Option or operand errors are only fatal for special built-ins.
This change also makes errors from 'fc' non-fatal (I could not find any reasons
for this behaviour).
Somewhat independently from the above down-grade the error handling in the
shift built-in if the operand is bigger than $# from an error() call (which is
now fatal) to a return 1. I'm not sure if this should be considered a POSIX
"operand error", however this change is needed for now as we trigger that error
while building libncurses. Comparing with other shells, zsh does the same as
our sh before this change (write a diagnostic, return 1), bash behaves as our
sh after this commit (no diagnostic, return 1) and ksh93 and NetBSD's sh treat
it as a fatal error.
set +o can be used to reload previous settings, for this to work disabled
options must be printed as well or otherwise options that were set in the mean
time won't be turned off.
To avoid an excessively long output line I formatted the output to print only
six options per line.
Submitted by: Jilles Tjoelker
PR: 73500
benefit of scripts start out as: #!/bin/sh -- # -*- perl -*-
With this fix in place, we can commit a change to kern/imgact_shell.c
so FreeBSD will process the `#!' line in shell-scripts in a more
standard fashion.
PR: 16393
Mentioned on: freebsd-arch
work as expected when they have a "shebang line" of:
#!/bin/sh -- # -*- perl -*- -p
This specific line is recommended in some perl documentation, and I think
I've seen similar lines in documentation for ruby and python. Those
write-ups expect `sh' to ignore everything after the '--' if the first
thing after the '--' is a '#'. See chapter 19, "The Command-Line Interface"
in 3rd edition of "Programming Perl", for some discussion of why perl
recommends using this line in some circumstances.
The above line does work on solaris, irix and aix (as three data points),
and it used to work on FreeBSD by means of a similar patch to execve().
However, that change to execve() effected *all* shells (which caused
other problems), and that processing was recently removed.
PR: 16393 (the original request to fix the same issue)
Reviewed by: freebsd-current (looking at a slightly different patch)
MFC after: 1 week
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
they already are.
o Change
int
foo() {
...
to
int
foo(void)
{
...
spaces reserved by the header files it includes.
mkinit.c still produces C code with redundant declarations, although
they are more harmless since they automatically derived from the right
places.
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.
getopts should now work as expected. This fix was in the NetBSD
code that I was merging from but missed getting into FreeBSD's
version because of 'drain bamage' on my part.
Submitted by: NetBSD, joerg
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
sh -c [-aCefinuvx] command_string [ command_name [argument ...] ] 1
4.56.3 Options
-c Read commands from the command_string operand. Set the
value of special parameter 0 (see 3.5.2) from the value of
the command_name operand and the positional parameters
($1, $2, etc.) in sequence from the remaining argument
operands.
Pointed out by: Kaleb Keithly (kaleb@x.org)
