I'm writing a gtk program and I try to take advantage of GSetings to store my own program settings. But the program failed at the statement "GSettings *settings = g_settings_new(SCHEMA);", with a message from the termial which said "Settings schema '.' is not installed". Must I install a settings schema before I create a GSettings object? If do, how to do that? If not, what should I do to store my settings? Is there a better way than using GSettings?
You guessed right; you have to install the schema before it will work. This is annoying because you can't run your program from your development directory without installing it anymore. Fortunately, it's easy to do right if you use Autotools:
In configure.ac, include the line
GLIB_GSETTINGS
and then put this in Makefile.am:
gsettings_SCHEMAS = org.my-domain.gschema.xml
#GSETTINGS_RULES#
where org.my-domain is a reverse domain name, used to identify your schema.
Related
How can I lock my Perl script, list I have to do
Prevent Others from read or write Perl Script.
They should have only Permission to Executing the Perl script.
This depends on your operating system, which you haven't specified.
Typically, this is not possible.
On a UNIX based system (such as Linux or Mac OS) there are three permissions that can be given to users, groups and everyone: Read, Write, and Execute.
You can remove Write permission easily enough, but Read permission is required to allow the script to be executed.
(I assume you would experience a similar problem on Windows).
The only work around I can think of would be to rewrite the script as a webservice. Then the HTTP server would need to be able to read it, but the users themselves would not.
If the system at hand is Linux/Unix and you have administrative access then you can use sudo.
With the following line in /etc/sudoers, anyone would be able to run, as author1, any executable file in the public_bin folder:
ALL ALL = (author1) /home/author1/public_bin/*
However, take a look at man sudoers to understand implications wrt. environment and command line arguments.
755 is the *nix permission you'll need. This will give the owner full access and other read and execute.
As other has said, there is no way to make your code unreadable. However,can you obfuscate you code so only a reasonably good programmer could decode it. There are online tools, if you search "perl obfuscate" on bing you'll get some good results; these tools will mean no module is required. Or my personal favorite is the module Acme::Bleach.
I am not sure this is clear to me and if is neat for my system. I'm aware of the ~/.zhrc file where I can store alias and paths, but today after installing node via brew I was asked to put this: export PATH="$HOME/.npm-packages/bin:$PATH" in my ~/.bash_profile file, which it doesn't exist, thus in my effort to keep my system clean I putted it in the former file but emacs complaint. Now, I removed it and putted it, after creating, in the ~/.bash_profile. Is that OK to keep both in the home directory?
You need to provide the exact wording of whatever error or warning message you
get from emacs to ensure accurate or better answers. However, I will make a
guess and assume the warning you are getting is from the exec-path package.
This package has a check, which you can disable, that looks to make sure you
have variables defined in the correct init file.
In general, most shells support two types of configuration files
Startup or Login init files
Interactive shell init files
The difference is how often or when the files are sourced (loaded). To
understand the difference, you really need to understand when a shell is run and
the relationship between each shell. I'll try to give a vary high level
explanation, but you really should read the manual page for the particular shell
you are using.
Think of your environment as a tree of shell processes. When you login to the
system, a login shell is created. This shell will be the parent of all the other
shells you create. Each time you run a command, it is executed in a new shell
(this isn't 100% accurate, but is accurate enough to explain the main
points). So when you open a terminal, it runs another shell which is a child of
your login shell. When you execute various commands, the system creates a new
shell and runs that command inside the shell. These are all children of your
parent login shell. Some shells only exist for a short period of time (as long
as it takes to execute the command), others may last for hours, days or possibly
weeks (such as the shell that emacs is running in).
The important point to keep in mind is that child shells inherit various
settings from the parent shell. The idea of the 'export' command you will see in
front of some variables is actually a command to the shell telling it to export
the variable to child shells. For example, if we have a line like
export PATH=/usr/local/bin:/usr/bin:/bin
what we are really doing is
PATH=/usr/local/bin:/usr/bin:/bin # set the variable
export PATH # make it available in child shells
We don't always want variables to be exported as some variables need to be reset
in the child shell itself. For example, the variable holding the prompt string.
It would not work to have this variable only defined in the login parent shell
if you want the prompt to have dynamic components, such as the current
directory, date or time. We want these types of variables to be defined in each
shell when it is created.
To handle this, shells have the two different init files. The login init files
are only sourced for the parent shell and are particularly useful for setting
variables that will be common to all child shells. the per-shell init files are
sourced for every new shell and are best used for setting things which need to
be updated or changed each time a shell is started. There are also other shell
configuration files which can be used for other special purposes, such as when
you log out or log off a system, or to just put alias definitions in etc.
Once upon a time, it made a big difference where you put your variables as there
was a performance hit when sourcing these init files. If the per-shell init file
was too large and consumed too many resources, the whole performance of your
environment could be affected. This is largely less of an issue these days due
to increased processing speeds. Unfortunately, because many people didn't
understand the role and relationships between the different shell configuration
files, there is lots of incorrect or misleading information out there regarding
where values should be set. People often advise setting variables in (for
example) bashrc when they should be set in the bash__profile=. The confusion is
partly caused by the fact you can add a variable to bashrc and it will work when
you test it (usually because your test involves forking a new child shell) and
putting it in your bash_profile will only work after the next login.
There are also some platform differences which make things a little less
clear. For example, under OSX, there is actually a special file in the /etc
directory where you should add additional path components (I'm not on a mac just
now, but it is something like /etc/paths or a per path component file in
/etc/path.d). This is done so that you have a global place to set paths which
will ensure desktop processes, such as the dock, which do not run as a child
process of your login shell, are able to be set.
As a general rule, most variables can go in the login profile, with the
exception of variables relating to the prompt or other variables which have a
dynamic content i.e. content which changes depending on time, directory
location or other tracking of interactive actions which are specific to a shell
instance.
Setting of the path (noting OS differences as described above) should go into
the profile or login configuration file. Under bash, this is .bash_profile and
under zsh, it is typically .zprofile. As bash has become the most common shell,
documentation etc often advises adding things to .bash_profile. If your running
zsh, then add the same information using .zprofile.
As you have said you don't have a.bash_profile, but you do have a zshrc file, I
am assuming you are running zsh rather than bash as your login shell. This being
the case, you need to add that path setting to .zprofile in your home
directory. The exec-path package is complaining because you added it to
zshrc/bashrc, which are not the correct place to set path variables. If your
running under OSX, you really need to add the path to the correct file in /etc
(you will need to check the OSX documentation as I cannot remember the precise
filename).
I have an error with perl while trying to CREATE a file called .envfile in the root dir / (only for UNIX). Permission denied, which is understood. But, is there a way to write this file? I need to do it without any modules, just with a built-in functions. I expect for using chmod, but... honestly, have no idea of how to implement it in the same thread SAFELY.
I need this file to write in it my own ENVs for my software (as it is a big project with many dirs and needs to operate with many own ENVs).
Trying simple:
my $filename = '.envfile';
open FH, '>', $filename or die $!;
print FH "some data\n";
close(FH);
Apache says: Permission denied at /var/www/cgi-bin/env.cgi line 41.
Any help appreciated!
Thanks!
If I understand the question correctly, it appears that you also control the software which will ultimately read the file you're trying to create. Is that accurate? If so, change the program to get its environment from somewhere else. Where else? Preferably a new directory, so that you can make it writable by your web server without affecting anything else. I'd probably use /etc/myprogram (because /etc is the standard place for configuration files) or /var/local/myprogram (because /var is the standard place for persistent data files). But not an existing directory which is and should remain writable solely by root.
Short of exploiting a security flaw, Perl does not allow you to sidestep filesystem security (permissions). And that is a Good Thing. If it were allowed, it would mean that anyone who finds an exploit in your Perl code could then change any file on your computer, potentially replacing it with the most malicious code ever written.
Thus, the only way that your Perl can create a file in / is if it runs as root or uses su/suid to run some other program as root. And you really, really, really do not want CGI scripts or web applications running as root because, unless you do everything absolutely perfectly in your code, and there are no exploitable bugs in perl itself, or apache, or the kernel, then, by running your web code as root, you're potentially handing root access to any random script kiddie on the internet.
If you really, truly, absolutely have no choice other than to have web-accessible code write arbitrary files to /, then the least-bad, least-insecure way to do it would be to create a very tiny helper program which takes a file name and file contents as inputs, checks to verify that the named file does not already exist (so that an attacker can't use it to overwrite, say, your kernel), and then creates the named file with the provided contents. Aside from maybe a little additional sanity/security checking, it should do absolutely nothing else because the more complex this helper program is, the more likely it is to contain exploitable flaws. Then have the web code use suid to run the helper program, with suid configured to allow the web user (and only the web user) to run the helper program (and only the helper program) with no password.
But don't do that unless you really, truly, absolutely have no other option. It is not the best way to do it, it is the least bad way. Which means it's still a bad idea.
Create the file 'by hand' and set it's owner to the owner of the apache process, e.g.:
sudo touch /.envfile
sudo chown www-data:www-data /.envfile
sudo chmod u+rw /.envfile
You're executing your Perl program as a user without sufficient privilege. Run the Perl program using a user with sufficient privilege (e.g. using sudo or su).
I'm currently trying to get this script to work:
https://github.com/mj41/auto-unrar/blob/master/bin/unrar2.pl
The only problem is that I get the following error:
Entering directory 'Series'
Entering directory 'Series/SerieName'
Entering directory 'Series/SerieName/Season2'
Entering directory 'Series/SerieName/Season2/SerieNameS02E21.720p.HDTV.X264-DIMENSION'
Entering directory 'Series/SerieName/Season2/SerieNameS02E21.720p.HDTV.X264-DIMENSION/Sample'
Can't call method "List" on an undefined value at unrar2.pl line 973.
This line is rar_obj->List();
$rar_conf{'-verbose'} = $rar_ver if $rar_ver;
my $rar_obj = Archive::Rar->new( %rar_conf );
$rar_obj->List();
my #files_extracted = $rar_obj->GetBareList();
This is an old script, 3-4 years old and I changed a little like SHA1 to SHA and use Filesys::DfPortable; to Df
Does anyone know how I can fix this error :)?
EDIT:
I contacted the developer and he told me I needed to install a program that can handle rar commands. So how would I do that. I can't seem to be able to install unrar.
EDIT2:
What my problem is now, 2 of the 3 unrar packages aren't in my architecture, armhf.
To install the script yourself::::::::::::
https://github.com/jorricks/UNRAR
You need to pass the -archive parameter into the call to new() otherwise how will $rar_obj know which file it is supposed to be looking at?
I can't seem to be able to install unrar
That's not a particular good explanation of your problem. What did you try? What unexpected behaviour did you see?
From the tags on your question, it looks like you're running Debian. What do you see if you run sudo apt-get install unrar?
Update: My first comment was based on the code extract that you showed us. Looking at the full program code, I can see that %rar_conf has other values set in it (including the -archive option) before the section of code you gave us.
Looking at the source of the Archive::Rar module, it seems to assume that the program to use for dealing with the archives is called rar. So 7-Zip is not going to work.
When i try to put something on a git server it's givin' me an error:
"Reference to undefined variable USER"
In bash: echo $USER giving me correct answer.
What could it be?
It's eclipse with aptana-3 plugin (a whole pack)
A bash session might have the correct environment variable set.
But the native OS session might not (like a DOS session on Windows for instance).
Can you launch your aptana from a session which has just before set the correct value for USER?
If it still fails (like in this thread), try also to set the correct value for $HOME.
Update: Tracked down the issue. Looks like Eclipse is biting on ENV values that contain "${" in the value. A user was changing his command prompt to incude his username, hostname and pwd. After he commented it out of his .profile, it avoided the issue. As a result I added a bugfix to fix that in our development stream that should get into our next release.
--
Looks like a duplicate of https://aptana.lighthouseapp.com/projects/35272/tickets/1867-git-push-has-encountered-a-problem
I'm not able to replicate the issue, but if you could provide some more details on that ticket I can take a look, since I wrote all of our git support. It's likely that somehow something like $USER is sneaking into the git executable path, and when passed along to the launching infrastructure, it tries to interpret it as an eclipse launching variable (as opposed to a ENV var) that it can't resolve.