It was my understanding that grub supports a small subset of bash. Their documentation doesn't go into super detail, other than it "supports conditionals", etc.
I am trying to run a simple if.
grub> if [ "${myvar}" = "fred" ]; then
> echo "test"
> fi
error: can't find command `['.
Anybody have an idea? I am using grub2-efi 2.00.
You are missing a grub2 module in order to run if tests.
I'm running Gentoo on a PowerPC system (PPC64 G5 machine) and doing a default grub-mkconfig then booting from it gives me the error in your question.
Since bash has that syntax support, I figured it was simply a grub module that needed to be added (I had been doing work with grub modules recently).
tl;dr: You need to load the appropriate grub module and then the error goes away.
The first step is to find out what modules you have. For me, it's whatever is available in my /boot/grub/powerpc-ieee1275/ folder.
There's also modules in /usr/lib/grub/powerpc-ieee1275/.
I wrote up a list of modules I thought I needed:
normal
eval
read
test
test_blockarg
trig
true
I then added them to my /etc/default/grub file:
GRUB_PRELOAD_MODULES="normal eval read test test_blockarg trig true"
I did not find an entry for GRUB_PRELOAD_MODULES in the config file, so I had to do some searching to find out how. I want these modules to be added every time I generate the grub config file, which means putting them in the 00_header portion of grub.
Then I recreated the configuration file:
grub-mkconfig -o /boot/grub/grub.cfg
The modules were in the header and things worked perfectly on reboot.
If I had to guess: you probably only need the test module to enable if statements.
Related
I'm trying to understand a few pieces associated with using bitbake to compile the linux image and generating a boot image that would be used to flash onto the processor.
How come bitbake virtual/kernel really works? Read through section 2.3 and it says recipes use PROVIDES parameter to add an extra provider, which indicates a recipe could be called in multiple ways (by its name, and by whatever PROVIDES is set to). But the kernel recipes (../poky/meta-bsp/recipes-kernel) I checked didn't have PROVIDES parameter let alone it being set to virtual/kernel.
Upon running bitbake virtual/kernel, how come a boot.img is being generated when it should only just be generating a linux binary i.e vmlinux for instance?
In one of the kernel .inc files, I see:
DEPENDS += " mkbootimg-native openssl-native kern-tools-native"
...
FILESPATH =+ "${WORKSPACE}:"
SRC_URI = "file://kernel \
${#bb.utils.contains('DISTRO_FEATURES', 'systemd', 'file://systemd.cfg', '', d)} \
${#bb.utils.contains('DISTRO_FEATURES', 'virtualization', 'file://virtualization.cfg', '', d)} \
${#bb.utils.contains('DISTRO_FEATURES', 'nand-squashfs', 'file://squashfs.cfg', '', d)} \
mkbootimg-native I reckon refers to the boot image recipe that the kernel recipe depends on, though shouldn't it be the other way around since the boot image should contain the kernel image itself?
lastly, is there a way to put debug prints in different recipe files to see if it's being invoked? I tried echo...to no avail
The recipes you checked probably had PROVIDES. Most if not all kernel recipes inherit kernel class (directly or via some other classes, such as kernel-yocto). The kernel.bbclass actually specifies PROVIDES for you, c.f. http://git.yoctoproject.org/cgit/cgit.cgi/poky/tree/meta/classes/kernel.bbclass#n8).
boot.img does not seem to be created by default for any machine. After a quick glance at the code, it seems that this is created by wic for images inheriting the image-live bbclass or by adding live to IMAGE_FSTYPES, c.f. http://docs.yoctoproject.org/ref-manual/classes.html#image-live-bbclass.
From a simple git grep in the poky git repo, it seems only bootimg-efi.py is actually doing something with a boot.img which is called by wic when the -b or --bootimg-dir argument is passed, which is enforced when using wic. So probably the boot.img artifact is created only for EFI machines and images.
If you use echo or printf or similar shell functions (or print in Python tasks) in your tasks, you can only see them in ${WORKDIR}/temp/log.do_<task> of your recipe. Otherwise, you can use bbplain, bbnote, bbdebug, bbwarn, bberror or bbfatal. This will print to both the logs and the console (depending on your log level which is configurable with -D (the more Ds, the higher the log level)).
I have a chef recipe that looks something like this:
package 'build-essential' do
action :install
end
cmd = Mixlib::ShellOut.new("gcc -dumpversion")
cmd.run_command
gcc_version = cmd.stdout.strip()
If I execute the recipe on a system where gcc is installed, the recipe runs fine without errors. However, if I run the recipe on a system which doesn't have gcc install I get the error 'no such file or directory - gcc'.
I came to know about the chef two-phases stuff when trying to find a solution to my problem. I was expecting the package installation to satisfy the gcc requirement. How can I tell chef that this requirement will be satisfied later and not throw an error at compile time?
I tried the following, but the attribute does not get updated.
Chef::Resource::RubyBlock.send(:include, Chef::Mixin::ShellOut)
ruby_block "gcc_version" do
block do
s = shell_out("gcc -dumpversion")
node.default['gcc_version'] = s.stdout.strip()
end
end
echo "echo #{node[:gcc_version]}" do
command "echo #{node[:gcc_version]}"
end
Any help is appreciated. Thanks.
So okay, a few issues here. First, forget that Chef::Resource::whatever.send(:include trick. Never do it, literally never. In this case, the ShellOut mixin is already available in all the places anyway.
Next, and more importantly, you've still got a two-pass confusion issue. See https://coderanger.net/two-pass/ for details but basically the strings in that echo resource (I assume that said execute originally and you messed up the coping?) get interpolated at compile time. You haven't said what you are trying to do, but you probably need to use the lazy{} helper method.
And last, don't store things in node attributes like that, it's super brittle and hard to work with.
I'm trying to run a Perl script called WyD using Cygwin on Windows. Cygwin is installed at C:\cygwin64, and WyD is installed at C:\wyd\wyd.pl. Both are in the Windows PATH environment variable as C:\cygwin64 and C:\wyd respectively.
When running WyD with bash/Mintty using:
wyd.pl -b -e -t -s 3 -o "OUTPUTTEDWORDLIST" "TARGETFOLDER"
...I get the following error:
Can't locate object method "init" via package "wlgmod::odt" (perhaps
you forgot to load "wlgmod::odt"?) at /cygdrive/c/WYD/wyd.pl line 284.
Sometimes wlgmod::odt is replaced with wlgmod::doc or any other document type, but running the script always generates that same basic error. A previous answer to this question recommended installing several dependencies, which turned out to be a mere copy-paste of an answer for Ubuntu systems, and didn't solve the error, so I've decided to start at the beginning and re-ask the question with more details. I also have all Perl packages in the Cygwin installer installed.
After everything I've tried and done to get this script working, I can personally think of two possible causes for the error. Think of these as a guide more than anything else.
The error above references line 284 in the wyd.pl script, so it's possible that something in that script is hardcoded so that it doesn't work with Cygwin/Windows, or just generally has a compatibility bug. I don't understand Perl, so I can't confirm this.
I notice that the installation of WyD at C:\wyd contains a folder called wlgmod, and that folder contains all the files that the above error seems to be looking for; doc.pm, html.pm, jpeg.pm, etc. If those files exist in that directory but bash is unable to find them, maybe it's due to the fact WyD needs to be run from within Cygwin itself. I've only recently thought about this possibility, and my knowledge of both Cygwin and WyD is too sparse to definitively know how both work. Is it even possible to run WyD from within the Cygwin folder? It's not a package so can't be installed as one, and therefore I'm not sure how that would work.
Here are the relevant sections of the script:
# Module hash containing module name and supported file extensions
# Multiple extensions are seperated using ';'
my %wlgmods = (
'wlgmod::strings', '', # only used with command-line switch
'wlgmod::plain' , '.txt', # used for all MIME text/plain as well
'wlgmod::html' , '.html;.htm;.php;.php3;.php4',
'wlgmod::doc' , '.doc',
'wlgmod::pdf' , '.pdf',
'wlgmod::mp3' , '.mp3',
'wlgmod::ppt' , '.ppt',
'wlgmod::jpeg' , '.jpeg;.jpg;.JPG;.JPEG',
'wlgmod::odt' , '.odt;.ods;.odp'
);
...
# Initialize possible modules
foreach(keys %wlgmods) {
eval("use $_;");
my $ret = $_->init(); # line 284
# If module failed, add errortext and remove from hash
if($ret) {
$retvals .= "$_: $ret\n";
delete $wlgmods{$_};
$ret = "";
}
}
I have been trying to run a shell script at boot time of freebsd. I have read all simmilar questions in stackoverflow and tried. But nothing is worked. This is the sample code that i tried is dummy.
#!/bin/sh
. /etc/rc.subr
name="dummy"
start_cmd="${name}_start"
stop_cmd=":"
dummy_start()
{
echo "Nothing started."
}
load_rc_config $name
run_rc_command "$1"
Saved with name of dummy.
Permissions are -r-xr-xr-x.
in rc.conf file made dummy_enable="YES".
The problem is, when i rebooted my system to test, dummy file is not there. So script is not executing. what else need to do run my dummy script.
SRC:http://www.freebsd.org/doc/en/articles/rc-scripting/article.html#rc-flags
You need to add rcvar="dummy_enable" to your script. At least for FreeBSD 9.1.
Call your script with parameter rcvar to get the enabled status:
# /etc/rc.d/dummy rcvar
# dummy
#
dummy_enable="YES"
# (default: "")
And finally start it with parameter start - this won't start the service/script unless dummy_enable is set in /etc/rc.conf (or /etc/rc.conf.local, or /etc/defaults/rc.conf)
# /etc/rc.d/dummy start
Nothing started.
One possible explanation is that rcorder(8) says:
Within each file, a block containing a series of "REQUIRE", "PROVIDE",
"BEFORE" and "KEYWORD" lines must appear.
Though elsewhere I recall that if a file doesn't have "REQUIRE", "PROVIDE" or "BEFORE", then it will be arbitrarily placed in the dependency ordering. And, it could be that the arbitrary placement differs between the first run up to $early_late_divider and in the second run of those after $early_late_divider.
OTOH, is this a stock FreeBSD, or some variant? I recall reading that FreeNAS saves its configuration somewhere else and recreates its system files on every boot. And, quite possibly that /etc is actually on a ramdisk.
Also, /usr/local/etc/rc.d doesn't come into existence until the first port installing an rc file is installed.
This example routine generates two Throw::nocatch warning messages in the kernel window. Can they be handled somehow?
The example consists of this code in a file "test.m" created in C:\Temp:
Needs["JLink`"];
$FrontEndLaunchCommand = "Mathematica.exe";
UseFrontEnd[NotebookWrite[CreateDocument[], "Testing"]];
Then these commands pasted and run at the Windows Command Prompt:
PATH = C:\Program Files\Wolfram Research\Mathematica\8.0\;%PATH%
start MathKernel -noprompt -initfile "C:\Temp\test.m"
Addendum
The reason for using UseFrontEnd as opposed to UsingFrontEnd is that an interactive front end may be required to preserve output and messages from notebooks that are usually run interactively. For example, with C:\Temp\test.m modified like so:
Needs["JLink`"];
$FrontEndLaunchCommand="Mathematica.exe";
UseFrontEnd[
nb = NotebookOpen["C:\\Temp\\run.nb"];
SelectionMove[nb, Next, Cell];
SelectionEvaluate[nb];
];
Pause[10];
CloseFrontEnd[];
and a notebook C:\Temp\run.nb created with a single cell containing:
x1 = 0; While[x1 < 1000000,
If[Mod[x1, 100000] == 0,
Print["x1=" <> ToString[x1]]]; x1++];
NotebookSave[EvaluationNotebook[]];
NotebookClose[EvaluationNotebook[]];
this code, launched from a Windows Command Prompt, will run interactively and save its output. This is not possible to achieve using UsingFrontEnd or MathKernel -script "C:\Temp\test.m".
During the initialization, the kernel code is in a mode which prevents aborts.
Throw/Catch are implemented with Abort, therefore they do not work during initialization.
A simple example that shows the problem is to put this in your test.m file:
Catch[Throw[test]];
Similarly, functions like TimeConstrained, MemoryConstrained, Break, the Trace family, Abort and those that depend upon it (like certain data paclets) will have problems like this during initialization.
A possible solution to your problem might be to consider the -script option:
math.exe -script test.m
Also, note that in version 8 there is a documented function called UsingFrontEnd, which does what UseFrontEnd did, but is auto-configured, so this:
Needs["JLink`"];
UsingFrontEnd[NotebookWrite[CreateDocument[], "Testing"]];
should be all you need in your test.m file.
See also: Mathematica Scripts
Addendum
One possible solution to use the -script and UsingFrontEnd is to use the 'run.m script
included below. This does require setting up a 'Test' kernel in the kernel configuration options (basically a clone of the 'Local' kernel settings).
The script includes two utility functions, NotebookEvaluatingQ and NotebookPauseForEvaluation, which help the script to wait for the client notebook to finish evaluating before saving it. The upside of this approach is that all the evaluation control code is in the 'run.m' script, so the client notebook does not need to have a NotebookSave[EvaluationNotebook[]] statement at the end.
NotebookPauseForEvaluation[nb_] := Module[{},While[NotebookEvaluatingQ[nb],Pause[.25]]]
NotebookEvaluatingQ[nb_]:=Module[{},
SelectionMove[nb,All,Notebook];
Or##Map["Evaluating"/.#&,Developer`CellInformation[nb]]
]
UsingFrontEnd[
nb = NotebookOpen["c:\\users\\arnoudb\\run.nb"];
SetOptions[nb,Evaluator->"Test"];
SelectionMove[nb,All,Notebook];
SelectionEvaluate[nb];
NotebookPauseForEvaluation[nb];
NotebookSave[nb];
]
I hope this is useful in some way to you. It could use a few more improvements like resetting the notebook's kernel to its original and closing the notebook after saving it,
but this code should work for this particular purpose.
On a side note, I tried one other approach, using this:
UsingFrontEnd[ NotebookEvaluate[ "c:\\users\\arnoudb\\run.nb", InsertResults->True ] ]
But this is kicking the kernel terminal session into a dialog mode, which seems like a bug
to me (I'll check into this and get this reported if this is a valid issue).