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Removing double quotes from variables in batch file creates problems with CMD environment
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You have an extra double quote at the end, which is adding it back to the end of the string (after removing both quotes from the string).
Input:
set widget="a very useful item"
set widget
set widget=%widget:"=%
set widget
Output:
widget="a very useful item"
widget=a very useful item
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When creating a service with sc.exe how to pass in context parameters?
...= "<pathtobinaryexecutable>" [option1] [option2] [optionN]
The trick is to leave a space after the = in your create statement, and also to use " " for anything containing special characters or spaces.
It is advisable to specify a Display Name for the service as well as setting the start set...
What are the differences between a HashMap and a Hashtable in Java?
...table in Java:
Hashtable is synchronized, whereas HashMap is not. This makes HashMap better for non-threaded applications, as unsynchronized Objects typically perform better than synchronized ones.
Hashtable does not allow null keys or values. HashMap allows one null key and any number of null va...
Bash script to set up a temporary SSH tunnel
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You can do this cleanly with an ssh 'control socket'. To talk to an already-running SSH process and get it's pid, kill it etc. Use the 'control socket' (-M for master and -S for socket) as follows:
$ ssh -M -S my-ctrl-socket -fnNT -L 50000:localhost:3306 jm@sampledomain....
What does send() do in Ruby?
...hod reacts (because its name matches the first argument).
Practically speaking, those lines are equivalent:
1.send '+', 2
1.+(2)
1 + 2
Note that send bypasses visibility checks, so that you can call private methods, too (useful for unit testing).
If there is really no variable before send, th...
What does “program to interfaces, not implementations” mean?
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Interfaces are just contracts or signatures and they don't know
anything about implementations.
Coding against interface means, the client code always holds an Interface object which is supplied by a factory. Any instance returned by the factory would be of type Interface which a...
DateTimePicker: pick both date and time
Is it possible to use DateTimePicker (Winforms) to pick both date and time (in the dropdown)? How do you change the custom display of the picked value? Also, is it possible to enable the user to type the date/time manually?
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What's the effect of adding 'return false' to a click event listener?
Many times I've seen links like these in HTML pages:
15 Answers
15
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Relationship between hashCode and equals method in Java [duplicate]
...ts is calculated according to both .equals() and .hashCode(), for instance keys in a HashMap.
As its name implies, it relies on hash tables, and hash buckets are a function of the object's .hashCode().
If you have two objects which are .equals(), but have different hash codes, you lose!
The part ...
Possible to perform cross-database queries with PostgreSQL?
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Note: As the original asker implied, if you are setting up two databases on the same machine you probably want to make two schemas instead - in that case you don't need anything special to query across them.
postgres_fdw
Use postgres_fdw (foreign ...