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Meaning of “[: too many arguments” error from if [] (square brackets)
...t find any one simple straightforward resource spelling out the meaning of and fix for the following BASH shell error, so I'm posting what I found after researching it.
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How to install a gem or update RubyGems if it fails with a permissions error
... using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
27 Answers
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Meaning of -
I am new to XML and I am trying to understand the basics. I read the line below in "Learning XML", but it is still not clear, for me. Can someone point me to a book or website which explains these basics clearly?
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How do I use boolean variables in Perl?
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@BlueWaldo: you can also use cmp and <=> when comparing and assigning the results of the comparison to a scalar. $var = $var1 cmp $var2; 'cmp' and '<=>' (used for numeric comparisons) returns -1, 0, or 1 if left argument is less than, equal to,...
StringIO in Python3
I am using Python 3.2.1 and I can't import the StringIO module. I use
io.StringIO and it works, but I can't use it with numpy 's genfromtxt like this:
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What are the differences between Generics in C# and Java… and Templates in C++? [closed]
I mostly use Java and generics are relatively new. I keep reading that Java made the wrong decision or that .NET has better implementations etc. etc.
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Ge...
In Windows Azure: What are web role, worker role and VM role?
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EDIT 3/3/2013 - updated to reference UDP endpoints, Virtual Machines, and more languages
EDIT 6/6/2013 - updated to reflect the discontinuation of VM Role, and update to web/worker role baseline OS images to Windows Server 2012
Good link by @Vladimir. A bit more clarification: All roles (web,...
What is the difference between Non-Repeatable Read and Phantom Read?
What is the difference between non-repeatable read and phantom read?
9 Answers
9
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How to permanently set $PATH on Linux/Unix? [closed]
... session. In case of the shell script you must use a specific shell syntax and export or set commands.
System wide
/etc/environment List of unique assignments, allows references. Perfect for adding system-wide directories like /usr/local/something/bin to PATH variable or defining JAVA_HOME. Used ...