I've recently had to compile a program (Riak) from source since they don't have a repo available for Ubuntu 16.04 yet.
I've compiled the program and copied it to /opt/riak where it works fine.
Since this program requires sudo privileges, I've decided to symlink /opt/riak/bin/riak to /usr/local/bin/riak instead of adding the variable to the path via a profile.d file (because in order to work with sudo I'd have to remove env_reset from /etc/sudoers which I rather not do).
The error I get is the following:
/usr/local/bin/riak: 8: .: Can't open /usr/local/bin/../lib/env.sh
Shouldn't the symlink execute the file from the original's working directory? Is there a way to make it work?
The error message is almost self explanatory. Apparently the riak executable is trying to find a file called env.sh using a path relative to its own, namely ../lib/env.sh. Originally, this would resolve to the following path: /opt/riak/bin/../lib/env.sh, which is the same as /opt/riak/lib/env.sh. But now is trying to find the file at /usr/local/bin/../lib/env.sh which is the same as /usr/local/lib/env.sh and obviously the file is not there.
You have the following options (in order of preference):
Leave the program in /opt and invoke it from there
Leave the program in /opt and create a small wrapper shell script in /usr/local/bin that calls the original executable (see at the end of this post).
Recompile the program passing the right parameters to its configure script (e.g. --prefix=/usr/local) so that it works from /usr/local.
I would recommend against option 3; I prefer to let the /usr directory be managed by the distos package manager. If I have to compile something myself, I prefer to put it in a dedicated directory bellow /opt. This way, if I want to remove it later on, I can just delete that directory.
Example wrapper script for option 2:
#!/bin/bash
exec /opt/riak/bin/riak "$#"
Related
I have a dynamic linker which is /lib64/libc.so.6
I stupidly renamed it to /lib64/libc.so.6.old and now NO commands work.
I cannot do ls or mv to rename it back.
I can run ldconfig but it says permission denied and I cannot run sudo or su - What on earth can I do to fix this? I am running Oracle Linux redhat 6.7
LD_PRELOAD=/lib64/libc.so.6.old mv /lib64/libc.so.6.old /lib64/libc.so.6
Start from a recovery/install iso and rename the file back.
If you can't reboot or don't have physical access to the machine you could try to install a compiled version of BusyBox https://busybox.net/FAQ.html#getting_started and use its su and mv commands. Since BusyBox is statically linked it should work without libc.so.
Go to single user mode, mount the file system with rw, since you know the location of the renamed file move /lib64/libc.so.6.old /lib64/libc.so.6
I would also propose a workaround with a mount point as already mentioned by #wildplasser.
You can make majority of command line tools working again if you have a mounted directory on your broken host. If you are lucky to have one then all you need is to upload the libc-x.yz.so (which you can take from another host of from Internet) on the share, rename it there to libc.so.6 and add the mounted directory to LD_LIBRARY_PATH.
If the version x.yz is the same as for the one which you thoughtlessly moved then the commands like ls, cp etc. will work again in the console where you set LD_LIBRARY_PATH. You should not logout from this console, because you won't be able to login again.
! Be aware that setuid command line tools won't work (see https://askubuntu.com/a/1029363/832810). Unfortunately "sudo" is one of them, this is why you won't be able to put back easily your long-suffering .so (unless you have a root# console). However it gives you a possibility to save all data and finish all actions before you do some hard restore.
If you managed to do the above-mentioned trick and you have enough time you can try to build a statically linked version of "sudo" as suggested on https://askubuntu.com/a/1030475/832810 (probably even build on another host and copy through NFS) and move the .so back using it.
I was trying to follow the instructions here to get drush installed on cygwin:
https://www.drupal.org/node/1432756#comment-11184267
However, running "drush" from my drupal project's folder did nothing (it didn't tell me -bash: this_command_I_made_up: command not found as it does for a command that doesn't exist).
Eventually I tried to run the symlink command like this:
ln -s /usr/local/src/drush/drush.bat /usr/bin/drush.bat
instead of this:
ln -s /usr/local/src/drush/drush.bat /usr/bin/drush
In other words, I added the .bat suffix to the filename path (drush.bat) instead of leaving it as plain old drush. Now I get results as I expect when running drush commands from my drupal project folders, but I have to type in drush.bat instead of drush when running drush commands.
I was just wondering if anyone could shed some light on the situation as to why the plain old drush symlink without the .bat suffix doesn't work. Thanks!
You may need to make the src/drush/drush.bat executable. If the symlink you make has a .bat extension (or .exe, etc.), it will automatically be executable in cygwin.
For files without extensions, the file must be marked executable.
For symlinks without extensions, the source (src/drush/drush.bat) must be marked executable.
To mark a file executable, use the command chmod +x src/drush/drush.bat.
I have recently installed a webframework play (http://www.playframework.com/) and want to have the play executable in the system path ie $PATH. But ubuntu already defines a command called play. How do I overwrite the system defined command with my framework binary path so that command play on commandline calls my framework rather than the old application.
Installation: I downloaded zipped file of the framework and upzipped in one of my personal folder which contains the docs and the executable.
Never alter the contents of installed packages. Such changes can provoke hard to find problems in the system and anyway, they will most likely be overwritten again in subsequent updates. There are other alternatives:
obviously you can chose another name for your executable
place the executable in another part of your $PATH if its a "personal installation", typically ~/bin is used for such approach. Remember that the order of entries in the $PATH variable is important, first come first serve.
use the traditional /usr/local/bin location for locally added "wild" installations, this way there is some form of clean separation between clean packages and wild installed files inside the system
store your software in some other location and prepend that to your personal or system wide $PATH variable
store your executable under another name and create an alias (see man alias for an explanation) for it which allows to call it by some name that "hides" the original command this way. For this the executable can be addressed with an absolute path, so it dies not have to be found inside the $PATH variable.
In my personal opinion options 2. and 5. and the best if it comes to "personal installations".
If you are sure you'll never use the original play command, you could just remove the binary. But in general, this isn't a good idea, since some system component you don't think of might need it, and the next update will probably restore it.
The best thing to do is to prepend the directory of your play command to the PATH, for example, using PATH=/opt/framework/bin:$PATH in your .profile (assuming your play command installs to /opt/framework/bin/play), or the script that starts your web server, or wherever you need your play command.
Remember that does not make your play command global. A common mistake is to add the path in their .profile file, then call the program from crontab - crontab scripts will not execute .profile or .bashrc.
I'm making a simple game for Ubuntu and to update the highscore list, it needs a single file at runtime, called 'highscores.bin'.
I wish to put this file at
/home/(USER)/.game_name
I've researched a little and found that from inside a Makefile i can get the environment variable $USER.
So in the Makefile, at the 'install' target, i've added:
mkdir -p $(DESTDIR)home/$$USER/.game_name
But when i run 'sudo make install', the Makefile installs it as:
/home/root/.game_name
How can i get the (non-root) user name in a Makefile?
P.S.: I'm writing the Makefile by hand. No ./configure
P.S.2: I dont want to do
mkdir -p ~/.game_name
because i want to be able to change DESTDIR if i want to install to a temporary directory.
Well, if you want that file during runtime I would recommend that you create it during runtime. The Makefile is considered only during compile time. This is obviously a problem if the program is compiled and then executed by different users, some of which may not even exist at compile time.
During runtime you can get the home directory as shown here (if you are using C/C++). Then you can check for existance of the highscore folder/file and create it if you need to. If you want a highscore file for all users, you should put it in the home directory of a special user, but rather somewhere else in the file system. This is for example done by the game xjump.
And about your Makefile, the $USER variable is translated to root because of the sudo command on
sudo make install
The user actually running make is the superuser: root.
You want to install your program for every users? So it's better if you create the /home/user/.game_name directory when the user run the game, not when root installs it. Otherwise, only the user who call sudo make install will have it's highscore list. If you have only one user, do not install it system-wide, but in the user directory.
I suggest to initialize users files at game first run. So every users, even users that didn't exist when the game was installed, can have their highscore list. You can add the initializing code into your game (c++, java or anything else) or just call an external script that does it (not so elegant). Avoid to create user-related files at installation time.
I've written a C++ program (command line, portable code) and I'm trying to release a Linux version at the same time as the Windows version. I've written a makefile as follows:
ayane: *.cpp *.h
g++ -Wno-write-strings -oayane *.cpp
Straightforward enough so far; but I'm given to understand it's customary to have a second step, make install. So when I put the install: target in the makefile... what command should be associated with it? (If possible I'd prefer it to work on all Unix systems as well as Linux.)
Installation
A less trivial installer will copy several things into place, first insuring that the appropriate paths exists (using mkdir -p or similar). Typically something like this:
the executable goes in $INSTALL_PATH/bin
any libraries built for external consumption go in $INSTALL_PATH/lib or $INSTALL_PATH/lib/yourappname
man pages go in $INSTALL_PATH/share/man/man1 and possibly other sections if appropriate
other docs go in $INSTALL_PATH/share/yourappname
default configuration files go in $INSTALL_PATH/etc/yourappname
headers for other to link against go in $INSTALL_PATH/include/yourappname
Installation path
The INSTALL_PATH is an input to the build system, and usually defaults to /usr/local. This gives your user the flexibility to install under their $HOME without needing elevated permission.
In the simplest case just use
INSTALL_PATH?=/usr/local
at the top of the makefile. Then the user can override it by setting an environment variable in their shell.
Deinstallation
You also occasionally see make installs that build a manifest to help with de-installation. The manifest can even be written as a script to do the work.
Another approach is just to have a make uninstall that looks for the things make install places, and removes them if they exist.
In the simplest case you just copy the newly created executable into the /usr/local/bin path. Of course, it's usually more complicated than that.
Notice that most of these operations require special rights, which is why make install is usually invoked using sudo.
make install is usually the step that "installs" the binary into the correct place.
For example, when compiling Vim, make install may place it in /usr/local/bin
Not all Makefiles have a make install