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What does set -e mean in a bash script?
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From help set :
-e Exit immediately if a command exits with a non-zero status.
But it's considered bad practice by some (bash FAQ and irc freenode #bash FAQ authors). It's recommended to use:
trap 'do_something' ERR
to run do_something function when errors occur.
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Why historically do people use 255 not 256 for database field magnitudes?
...ric reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
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Effect of a Bitwise Operator on a Boolean in Java
The bitwise operators are supposed to travel variables and operate on them bit by bit. In the case of integers, longs, chars this makes sense. These variables can contain the full range of values enforced by their size.
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C: differences between char pointer and array [duplicate]
...ent scope's stack space, it is unspecified exactly where it will be stored and should not be modified.
Edit: As pointed out by Mark, GMan, and Pavel, there is also a difference when the address-of operator is used on either of these variables. For instance, &pmessage returns a pointer of type ...
C programming in Visual Studio
...t menu I can choose between Visual Basic, Visual C#, Visual C++, Visual F# and others but I don't see "C" or "Visual C".
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Dropping Unique constraint from MySQL table
... @Ankur Mukherjee: I forgot to mention: You have to change tbl_name and index_name to the name of your actual table and the name of the actual index, respectively. You can see the names in MySQL Query Browser. You can also do SHOW CREATE TABLE tbl_name.
– Mark Byers
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Revert to Eclipse default settings
...nces>Java>Editor. Click on Syntax Coloring. Click "Restore Defaults" and "Apply". Then, navigate to General>Editors. Click on Text Editors. Click on "Restore Defaults" and "Apply".
I had the same issue and the above steps cleared up my problem. Also, the Show line numbers check box is on t...
Best way to define private methods for a class in Objective-C
I just started programming Objective-C and, having a background in Java, wonder how people writing Objective-C programs deal with private methods.
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What are copy elision and return value optimization?
...to a copy or move constructor is elided, that constructor must still exist and must be accessible. This ensures that copy elision does not allow copying objects which are not normally copyable, e.g. because they have a private or deleted copy/move constructor.
C++17: As of C++17, Copy Elision is gua...
PhoneGap Eclipse Issue - eglCodecCommon glUtilsParamSize: unknow param errors
I have just started on phonegap and trying to setup first basic minimal project in eclipse. I followed through the phonegap docs at http://docs.phonegap.com/en/edge/guide_platforms_android_index.md.html#Android%20Platform%20Guide
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