Ruby: All Errno::ERROR constants inherit from SystemCallError

To catch all possible exceptions from a network call, we need to rescue many error classes like this:

rescue SocketError, Errno::ECONNREFUSED, Errno::ECONNRESET, Errno::ECONNABORTED, Errno::EHOSTUNREACH, OpenSSL::SSL::SSLError, MyHttpLib::BadResponse

You can shorten this a bit by rescuing SystemCallError Show archive.org snapshot , which is a base class for all Errno:: exceptions:

rescue SocketError, SystemCallError, OpenSSL::SSL::SSLError, MyHttpLib::BadResponse

Some high-level HTTP client libraries convert these errors into a single base class for easier handling E.g. Http.rb Show archive.org snapshot provides a HTTP::Error class and you only need to rescue this one class.

Henning Koch

makandra.com

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Almost 6 years ago

Henning Koch

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Fix [RubyODBC]Cannot allocate SQLHENV when connecting to MSSQL 2005 with Ruby 1.8.7. on Ubuntu 10.10

I followed this nice guide Connecting to MSSQL with Ruby on Ubuntu - lambie.org until I ran in the following errors:

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``...

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=> {}
>> 
?> er...

Posted by Henning Koch to makandra dev (2018-06-08 09:35)

Ruby: All Errno::ERROR constants inherit from SystemCallError

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