What's the simplest way to find the path to the file in which I am "executing" some code? By this, I mean that if I have a file foo.py that contains:
print(here())
I would like to see /some/path/foo.py (I realise that in practice what file is "being executed" is complicated, but I think the above is well defined - a source file that contains some function that, when executed, gives the path to said file).
I have needed this in the past to make tests (that require some external file) self-contained, and I am currently wondering if it would be a useful way to locate some support files needed by a program. But I have never found a good way of doing this. The inspect module sounds like it should work, but you seem to need a class or function that is defined in that module.
In particular, the module instances contain __file__ attributes, but I can't see how to get the "current" module. Objects have a __module__ attribute, but that's the module name, not a module instance.
I guess one way is to throw and catch an exception and inspect the contents, but that seems like hard work. Surely there is a simple, easy way that I have missed?
To get the absolute path of the current file:
import os
os.path.abspath(__file__)
To get content of external file distributed with your package you could use pkg_util.get_data()(stdlib) or pkg_resources.resouce_string() (setuptools) to support execution from zip-archives or standalone executables created by py2exe, PyInstaller or similar, example.
Related
I am trying to find a read that differentiates the advantages of using a Path object over the File object in java. I see a comparison of the API here http://docs.oracle.com/javase/tutorial/essential/io/legacy.html but don't really see the real advantages anywhere. Any pointer will be appreciated!
Generally one could say that both classes have different focus.
File is designed for file handling (creating, deleting, ...) while Path is focused on filename parsing.
File seems to have most functionality of Path included but there may be special cases where Path suits better.
Please see the documentation sites (especially methods overview) java.nio.File and java.nio.file.Path for further information.
This is my code:
SoundPlayer player = new SoundPlayer("sound/music.wav");
player.Load();
player.Play();
The sound exists in directory, but when I build it, the program throws FileNotFoundException.
What should I do?
Make it a habit to always use System.IO.File.Exists() before actually asking .NET to use a file. This can save you from some run-time exceptions.
This is almost certainly because the relative path you have provided does not map to the current directory. I'm not even sure if that kind of forward-slash addresses is supported by SoundPlayer's constructor or by .NET in general. Anyway, you should always use System.IO.Directory functions to construct your full path and pass that to SoundPlayer.
I had some lua code with the following line:
JSON = loadfile("JSON.lua")()
The file JSON.lua is in the same directory as the lua code that line came from. This code worked for me for a while, and then, without my changing either the lua source, or the JSON.lua, or permission of any of the files, or the directory from where I was running the lua code, I started getting a nil error on that line. (I simply recall NO relevant changes that could have any impact on the lua code.)
Adding an assert revealed that the error was caused by the file not being found. Playing with file permissions, restarting my machine didn't resolve the issue, and pulling back code that I had checked in and was working perfectly did not resolve the error.
I resolved the error by changing the line above to provide the absolute path to that JSON.lua file.
Is there anything explaining why the code without the absolute path could have worked for a while and then stopped working?
Note: This behavior of working and then not working happened to me twice over a week. I am puzzled and though I have now found a fix, I am really curious as to the explanation for that intermittent behavior.
Lua uses package.path, whose default value comes from the environment variable LUA_PATH if it is set, as the list of directories to search. You can put . of the front of this list to load files from the current directory, or you can put your files in a path on the list.
A late answer on this, as I found exactly the same problem.
First, contrary to the previous answer, loadfile doesn't use the package.path search path. It only looks in the specified directory. And if you don't specify a directory, it only look in the 'current directory'. I can't explain exactly why it stopped working for you, but probably your Lua code is somehow being run with a different 'current directory' than previous.
There are two possible fixes: One is to specify an absolute path to loadfile.
JSON = loadfile("c:\\my_folder\\JSON.lua")()
The alternative fix depends on the particular library you're using, which I suspect is Jeffrey Friedl's Lua JSON lilbrary. Because this supports the newer Lua module mechanism, you can just load the module with require, which does support the package.path search path.
JSON = require("JSON")
I'd like to include code from another source file. Does anyone know how to do that?
If your file is called foo.pl, you can include it using
:- [foo].
or, equivalently and a bit more explicit
:- consult(foo).
or, if you're worried it may be loaded several times in a larger app
:- ensure_loaded(foo).
or, if you're using full-blown modules
:- use_module(foo).
though the exact name of the last predicate differs between Prolog versions.
If you want to include the file literally - similar to #include, use
:- include('file.pl').
Most of the time it is preferable to structure your program using
modules, though.
I have a huge project, whole written in C language and I have a single make file that is used to compile it. The project C files contains lots of capitalize problems in it's header files, meaning there are tones of header files that were miss-spelled in lots of C files.
The problem is I need to migrate this project to compile on Linux machine and since Linux is case sensitive I got tones of errors.
Is there an elegant way which I can run make file in Linux and tell him to ignore case sensitive?
Any other solution will be welcome as well.
Thanks a lot.
Motti.
You'll have to fix everything by hand and rename every file or fix every place with #include. Even if you have a huge project (comparable with linux kernel), it should be possible to do this during a hour or two. Automation may be possible, but manual way should be better - because script won't be able to guess which name is right - filename, or the name used in #include.
Besides, this situation is a fault of original project developer. If he/she wasn't sloppy and named every header in every #include correctly, this wouldn't happen. Technically, this is a code problem similar to syntax error. The only right way to deal with it is to fix it.
I think it takes not too long to write a small script, which goes thru the directories first, then replaces C headers. Explained:
Scan the headers' folder and collect filenames.
Make a lowercase list of them. You have now original and locased pairs.
Scan the C source files and find each line contains "#include"
Lowercase it.
Find the lowercase filename in the list collected and lowercased from headers.
Replace the source line with the one collected from headers.
You should put the modified files into a separate folder structure, avoid overwriting the whole source with some buggy stuff. Don't forget to create target folders during the source tree scan.
I recommend a script language for that task, I prefer PHP, but just it's the only server-side script language which I know. Yep, it will run for a while, but only once.
(I bet that you will have other difficulties with that project, this problem is not a typical indicator of high quality work.)
Well I can only tell you that you need to change the case of those header files. I don't know that there is any way you can make it automatic but still you can use cscope to do it in a easier way.
http://www.linux-tutorial.info/modules.php?name=ManPage&sec=1&manpage=cscope
You can mount the files on a case-insensitive file system. FAT comes to mind. ntfs-3g does not appear to support this.
I use the find all and replace all functionality of Source Insight when i have to do complete replacement. But your problem seems quite big, but you can try the option to replace every header file name in all occurences of source files using the
"Find All" + "Replace" functionality. You can use notepad++ too for doing the same.
A long time ago there was a great tool under MPW (Macintosh Programmer's Workshop) called Canon. It was used to canonize text files, i.e. make all symbols found in a given refernce list have have the same usage of upper/lower case. This tool would be ideal for a task like this - I wonder if anything similar exists under Linux ?