I'm trying to use a software library to run some computations. These computations can be customized using a few configuration files in its share directory. Unfortunately this library only provides hard coded paths to specific files in its (read-only) share directory which store these default configurations. Thus right now only a super-user or administrator could modify them. The library doesn't search for any user-local versions of these configuration files. I'd like to develop a wrapper tool which additionally takes a path to an alternate version of one of these configuration files in the users home directory and have that file somehow appear to "mask" the original file on the file system for the duration of process execution without actually modifying the original file in any way (since it can't). Is there a Linux tool I could use to do this sort of thing?
I'm probably just being very thick here, but it's not clear to me where I'm supposed to install 'new' user-specific programs on Windows 7 (and presumably Vista too, though I've not specifically looked at that scenario yet).
Under Windows XP (rightly or wrongly) we always installed our programs into folders under 'Program Files' and accepted that they'd be kind-of available to everyone. From what I can gather under Windows 7 I'm supposed to install my software under the user's AppData folder (possibly AppData\Local\MyApp). That makes a degree of sense, but the fact that this folder is 'hidden' by default means that we're going to have 'fun' talking our users through support stuff.
I want to install our software so that it's user specific (the Users bit in Windows 7 makes perfect sense) but I do want the user to be able to access it if required. Our program also includes a 'data' subdirectory which it needs to write into while it's running (embedded database), but as the program is intended to be single-user/standalone, the data folder being inside a user-specific folder isn't going to be a problem.
My problem is just that whole 'hidden folder' aspect of AppData. As much as I've trawled the MSDN, I can't work out where else I'm supposed to install user-specific programs. Taken one way it would seem to be something like AppData\Local\MyApp, and another way it would seem to be just as valid under the user's My Documents\MyApp equivalent.
Has anyone got a clear guide for where all this stuff goes? I found the MSDN docs confusing. :-)
Not really.
The directory that serves as a common
repository for application-specific
data for the current roaming user.
AppData is, surprisingly, for application data, not for installation (Click Once/Silverlight applications aside). You can, and should still install into Program Files, just don't expect to write into that folder.
You can install software into AppData if you want it to follow a user about in an Active Directory environment, which happens if you put it in AppData\Roaming (the SpecialFolder.ApplicationData location).
You can also install into AppData if you want the software to be available to just the user that installs it. This can be useful if, for example, you have multiple users on the same machine, who all want to run different versions of the software in complete isolation.
If you want settings to only apply on the local machine then you use AppData\Local, which is SpecialFolders.LocalApplicationData - this will make AD administrators very happy as the roaming profile size won't suddenly jump up 50Mb or whatever the size of your software is.
If you wanted to create settings which apply to all users then you're looking at SpecialFolders.CommonApplicationData
You should remember never to rely on the actual name of the directory - localisation issues mean this can change and the location does change with OS versions two. You should be using the special folder enumeration in your software, or the equivalent in your installer.
Could you not install into Program Files, but use AppData as it's supposed to be used, and store your database in there?
Windows 7 added the FOLDERID_UserProgramFiles known folder and by default this maps to %LOCALAPPDATA%\Programs. This is used by MSI when ALLUSERS=2 & MSIINSTALLPERUSER=1.
On Vista and earlier there is no canonical per-user application folder but just using %LOCALAPPDATA% is pretty common. Sadly MSI will just use %ProgramFiles% on these systems.
It's 2019, and I just installed Visual Studio Code (a Microsoft product) in the default folder of
%userprofile%\AppData\Local\Programs\Microsoft VS Code
This is probably for getting around the requirement to have an administrator or UAC prompt authorise the installation
Windows 7 folder structure is deeply inspired on Unix structure:
/usr/ -> C:\Program Files\ -> binaries: executables and dynamically linked
/etc/ -> C:\ProgramData\ -> global settings
/home/ -> C:\Users\ -> a folder for each user
~/.* -> C:\Users\Hikari\AppData\Roaming\ -> settings for each user
Windows has more folder, like My Documents for files with content produced by user, AppData Local and Roaming (which Unix usually handles with NFS).
It's about time for us developers to start using these structures. We must separate at least binary files that don't need to be replicated, global and user settings.
When a setup is installing an app, this setup should expect to have permission to write on Program Files. Once the setup is finished, Program Files should be writable only for other setups aiming to update binaries to other versions.
Please install executable files to the %programfiles% folder in Windows - a simple MSI based install package can perform an active setup for any new user who logs onto the machine to create the user specific files and folders in their profiles %appdata% folder. You see this behaviour for Internet Explorer, Adobe reader, etc. - It's the little MSI installer window that pops up the first time you log onto a machine which has those applications installed. - Thanks - a system admin :)
My opinion, for what it's worth, is that user-specific program files is just asking for trouble and is a damn stupid thing to do.
A much more sensible approach is to install different versions of your program to:
\Program Files\Your Program\Program_v0.1\Program.exe
\Program Files\Your Program\Program_v0.2\Program.exe
\Program Files\Your Program\Program_v0.3\Program.exe
\Program Files\Your Program\Program_v0.4\Program.exe
I would then place a bootstrapping launcher at:
\Program Files\Your Program\ProgramLauncher.exe
Then, the user application data folder will only contain data, including an INI/XML/Settings file that indicates the version of the program that this user is working with.
Such an approach satisfies the core tenant of keeping data and executing code separate, allows every user to run a specific version of the code, and offers a small amount of de-duplication by ensuring the same executable code is not copied multiple times across user folders.
Otherwise, go right ahead with installing programs to AppData and undoing the years it has taken us to achieve clean separation of code and data. I found this thread because I noticed that Chromium and DropBox are installing code to AppData. I'm going to uninstall those program, and change the permissions on my AppData folder to exclude execution to ensure I can easily spot other programs attempting the same BS.
I have a standalone server running Cygwin -- I did not setup this server, it was inherited. Anyway, I'd like to know what options the installing admin selected in the setup program.
I've read that I could look in /etc/setup, /etc/postinstall, or /etc/preremove but there are a lot of packages in those directories... same goes for the output of cygcheck -c.
I don't want to know every single library on the system... just how to duplicate the install. Is there a way to determine which packages were select in the GUI setup program?
Thanks!
Cygwin is pretty standalone. You should be able to archive up the entire Cygwin directory (and subdirectories) and move it to the same location on another system.
If you archive it up I recommend 7-zip. You can get it free here. The built in Windows archiver can create permission problems when an archive is extracted on a destination system. I recommend 7-zip for both archiving and unarchiving. If you use the built in Windows archiver and then move it to the new system and extract it - it will extract without errors. However you may find things don't actually work right while using some Cygwin applications
If you don't copy everything you won't move any of the original admin's custom changes.
Hi have an application running separateley (1 instance for customer) in different folders, 1 per each customer.
Each customer is a separate user on my machine.
At the moment I have the source code in each of these folders where I rebuild the code per each instance. Would it be better if I do something like the following?
create a shared folder where I build the code
deploy the binary in each user folder.
allow permission for each user to access the source code in READ ONLY mode.
when it is time to debug, by using gdb in each user folder will allow to read the source code and debug will happen.
Do you think that this could be a better approach or there are better practice?
My only concern is that each user has the chance to read the source code, but since the user will not access directly his folder (it is in my control) this should not trouble me.
I am using CENTOS 6.4, SVN and G++/GDB.
in different folders
There are no "folders" on UNIX, they are called directories.
I rebuild the code per each instance
Why would you do that?
Is the code identical (it sounds like it is)? If so, build the application once. There is no reason at all to have multiple copies of the resulting binary, or the sources.
If you make the directory with sources and binaries world-readable, then every user will be able to debug it independently.
Is it possible to install and run applications using the regular filesystem but make created files and changes written to a specific directory?
I want to make an application believe it is installed to the system root and remove it by just deleting one folder from my home directory. A lightweight solution would be great!
It should be possible by combining unionfs and namespace. Create a mount namespace (using unshare(1)), mount a unionfs over everything and run the application there (I haven't done it myself, so no example commands, sorry).
Take a look at mbox http://pdos.csail.mit.edu/mbox/
It intercepts system calls to a temporary directory which you can specify