I am a total newbie to programming and Ubuntu and Swift is my first language to learn.
I am learning with a book but I encountered a problem when I was supposed to build an application. Here is what I had to do:
Make a new directory called PMExample so that's easy mkdir PMExample
and then go to this directory cd PMExample.
Then I had to use ~/swift package init and got 2 directories called Sources and Tests and a file Package.swift.
So in the Sources folder there was one text file and I had to create another one to build an application.
And I did all those steps correctly, but now there is a problem. The book tells me to use swift build command. The book says that this will build the application and if all is well, I will have an executable application in the
PMExample/.build/debug directory named PMExample...
But after ~/swift build while being in the PMExample dir, there isn't any new directory called .build or anything. There are no errors popping up after using that ~/swift build command. Just nothing happens and I can't understand what am I doing wrong.
Thanks in advance.
But after ~/swift build while being in the PMExample dir, there isn't any new directory called .build or anything.
How do you know that? It is likely that you are not seeing the directory because it starts with a dot (it is called .build), therefore it is not shown by default with ls. You have to pass the -a argument to ls, such as in:
ls -a PMExample
Related
So some background, I'm installing Node on a host server, but it's a grid server not a server that's solely for my website.
The grid server doesn't have a root user/ administrative powers. So to install node I found this workaround: http://iantearle.com/blog/media-temple-grid-and-nodejs . It's a Linux Grid server, I've never used Linux so if someone could explain to me what the commands mean, especially: ./configure --prefix=~/opt/
Lastly I followed the steps but when I try to run the node command in the server it says node:command not found - which is why I'm trying to understand the steps. Thanks
To explain the process:
Configure
The configure script is responsible for getting ready to build the software on your specific system. It makes sure all of the dependencies for the rest of the build and install process are available, and finds out whatever it needs to know to use those dependencies.
Unix programs are often written in C, so we’ll usually need a C compiler to build them. In these cases the configure script will establish that your system does indeed have a C compiler, and find out what it’s called and where to find it.
Make
Once configure has done its job, we can invoke make to build the software. This runs a series of tasks defined in a Makefile to build the finished program from its source code.
The tarball you download usually doesn’t include a finished Makefile. Instead it comes with a template called Makefile.in and the configure script produces a customised Makefile specific to your system.
3.Make Install
Now that the software is built and ready to run, the files can be copied to their final destinations. The make install command will copy the built program, and its libraries and documentation, to the correct locations.
--prefix=~/opt/ -> will set the build directory to /home/yourhome/opt directory.
Now if you didnt get errors while doing those 3 steps explained above make sure you did the following:
nano ~/.bash_profile
export PATH=~/opt/bin:${PATH}
nano is a text editor and you are opening .bash_profile file with it.
you need to add export PATH=~/opt/bin:${PATH} in that file and save it using ctrl+x
Then restart your terminal.
Specified github repository for nodejs is outdated. use the following link instead.
git clone https://github.com/nodejs/node.git
P.S node:command not found usually happens when the program is not installed correctly or it's executable isnt in your terminal's PATH variable.
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 "$#"
Is there a way to prevent the rpmbuild command from reading the ~/.rpmmacros file? I want to add rpmbuild to a Make target and want to get a consistent build under any user account, regardless of the options somebody might have personally set in the rpmmacros file in his home directory.
How can I do this? Or, is that actually a bad idea?
If you're looking to get the a consistent build then the rpmmacros is only one part of the problem. The build may still differ simply because it's running on a machine with different things installed. Use mock to get a truly consistent build environment.
Solved this now this by setting $HOME to an empty directory while running rpmbuild:
mkdir $MY_DIST_DIR/dummyhome
HOME=$MY_DIST_DIR/dummyhome/ rpmbuild ...
rm -r $MY_DIST_DIR/dummyhome
Wow, let me first say that I've lost count how many answers I've found on this site. You guys are awesome!
So, my first-ever question I'm posting is rather basic so I hope it's not badly received. I did search to find an answer on google as well as here, but did not find an answer.
I just created a console app with code:blocks on linux, compiled it then ran within code:blocks. Works just fine. Then I opened linux bash shell, cd to where the binary was, then just tried running it from there, no dice. A linux buddy of mine came over and told me to try ./ preceeding it. Viola, that worked. I was dumbfounded because I thought ./ was only needed to execute shell scripts. I checked file permissions for the binary built by g++ and they are these: -rwxrwxr-x
I've found other tutorials on building the Hello World application with code:blocks and they also say to execute on the command line using ./
Why is this so? Also, how can I build a console application or any other binary application such that the ./ is not required to execute it? I'm assuming it's possible somehow seeing as the vast majority of the built-in linux commands, such as grep, etc do not require the ./ to execute.
Thanks, guys.
To run an executable on UNIX-like systems, you need to be aware of path resolution. If the path to the executable is not included in the PATH environment variable (and . sometimes isn't), you need to specify it yourself.
By appending . to PATH, like this:
export PATH=$PATH:.
you can run executables from the current working directory without adding ./. Note, however, this may be unsafe in a multi-user system, as other users can provide executables for you to run, in group or world writable directories, without your explicit permission(s).
Background:
I recently joined a software development company as an intern and am getting used to a new build system. The software is for an embedded system, and lets just say that all building and compiling is done on a buildbox. The building makes use of code generation using xml files, and then makes use of make files, spec files, and version files as well.
We develop on our own comps, (linux - mandriva distro) and build using the following methods:
ssh buildserver
use mount to mount drive on personal computer to the buildserver
set the environment using . ./set_env (may not be exactly that)
cd app_dir/obj (where makefile is)
make spec_clean
make spec_all
make clean
make
The Question:
I am a newbie to Code::Blocks and linux and was wondering how to set up a project file so that it can simply run a script file to execute these commands, instead of actually invoking the build process on my actual computer. Sort of like a pre-build script. I want to pair the execution of this script simply to Ctrl-F9 (build) and capture any output from the above commands in the build log window.
In other words, there is no build configuration or target that the project needs to worry about. I don't even need a compiler installed on my computer! I wish to set this up so that I can have the full features of an IDE.
Appreciate any suggestions!
put your script in a shell script file. E.g.,
#!/bin/sh
mount ... /mnt/path/buildserver
. ./set_env
cd app_dir/obj
make spec_clean
make spec_all
make clean
make
Say you name it as /path/to/my_build_script, then chmod 755 /path/to/my_build_script and invoke the following from your ssh client machine:
script -c ssh buildserver "path/to/my_build_script"
When finish, then check for the file typescript under current directory.
HTH