TortoiseSVN (Subversion) and Windows 7 file corruption

During a checkout of a Subversion tree on my Windows 7 installation I got quite a fair share of errors from TortoiseSVN, all of which ended with The file or directory is corrupted and unreadable.

After digging around a bit, I came across this blog post on the exact same problem. And subsequently I found there is a hotfix available from Microsoft on their page about . This hotfix will be in the upcoming service pack 1.

You might also be able to work around it by disabling indexing on the particular folder or drive. It solved it for me at least.

Visual Studio editor rulers

If you like to have a visual cue for, say, where the 80th column is then this page over at Stack Overflow details the various registry keys you might need to add as well as showing which extensions can do it for you. For VS 2010 Professional and up you can use the Productivity Power Tools, but it seems that Visual Studio 2010 Express has no guides support.

Sublime Text with 80 and 120 column rulers

For many programming languages we still like to use either 80 or 120 columns in our editors to ensure it fits easily on print, as well as to use it as an aid for ensuring concise code.

In Sublime Text you can set vertical rulers for this by going to Preferences > User File Preferences and add rulers 80 120 and save the file.

For Sublime Text 2 it’s again under Preferences > User File Preferences, but the configuration file is now in JSON format, so you need to add "rulers": [80, 120] and maybe you need to append a comma at the end if you have more configuration directives following it.

Mercurial 1.7, cacerts, and FreeBSD

So with recent Mercurial 1.7 releases HTTPS support was tightened, so you are bound to encounter a warning in the form of: warning: bitbucket.org certificate not verified (check web.cacerts config setting).

Now, on http://mercurial.selenic.com/wiki/CACertificates there are details on what to configure for certain operating systems. Given I use FreeBSD, I altered my $HOME/.hgrc as follows:

[web]
cacerts = /etc/ssl/cert.pem

For OpenBSD this should be in the same place since release 3.8. But apparently NetBSD does not have such a file in base.

PyCharm and external lint tools

PyCharm already has a number of features present in various tools to lint/check your source code with, but offers a way to hook up external tools. Under File > Settings is a section called IDE Settings. One of the headings here is called External Tools. Select this heading and then press the Add... button on the right hand pane to configure a new external tool.

In the Edit Tool window that now appeared fill in a name, e.g. PEP8 and a group name Lint and add a description. Next point the Program to the location of the pep8.exe executable, e.g. C:\Python27\Scripts\pep8.exe. For Parameters you need to use $FilePath and Working directory should be filled in by default. Once done, you can close it by pressing the OK button.

Now, pyflakes has no .exe or .bat file to accompany it. You will need to add a pyflakes.bat in your Scripts directory inside Python with the following contents:

@echo off
rem Use python to execute the python script having the same name as this batch
rem file, but without any extension, located in the same directory as this
rem batch file
python "%~dpn0" %*

Within PyCharm you follow largely the same settings as for pep8, however make sure to point to the batch file of pyflakes under Program. Close the external tools configuration windows by clicking OK twice. Under the menu heading Tools you should see an submenu heading Lint which, in turn, should contain two menu items: PEP8 and Pyflakes.

Now open a Python file, go to Tools > Lint > PEP8 and you should get output like the following in your Run (4) window:

D:\Python26\Scripts\pep8.exe D:\pprojects\babel\babel\tests\__init__.py
D:\pprojects\babel\babel\tests\__init__.py:16:1: E302 expected 2 blank lines, found 1

Process finished with exit code 1

Predefined macros

So with the GNU compiler you can use the preprocessor to get a list of the predefined macros:

$ cpp -dM /dev/null

or if you prefer to invoke the preprocessor via gcc itself:

$ gcc -dM -E - < /dev/null

This should give you a list similar like:

#define __DBL_MIN_EXP__ (-1021)
#define __FLT_MIN__ 1.17549435e-38F
#define __DEC64_DEN__ 0.000000000000001E-383DD
#define __CHAR_BIT__ 8
#define __WCHAR_MAX__ 2147483647

For Microsoft’s Visual C++ compiler I have only found pages like:

For Intel’s C++ compiler I found the following page with predefined macros.

And I find this interesting page with a lot of different compilers and their predefined macros to identify them and their versions, if any.

Edit: I also found how to do this with Clang:

$ clang -dD -E - < /dev/null