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How is malloc() implemented internally? [duplicate]
Can anyone explain how malloc() works internally?
3 Answers
3
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psql invalid command \N while restore sql
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Postgres uses "\N" as substitute symbol for NULL value. But all psql commands starts by backslash "\" symbol. So you can get this messages, when probably copy statement fails, but a loading of dump continues. This message is only false alarm. You have to search a lines before for reas...
How to create a directory in Java?
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-1: That is actually a really bad technique to create a directory. The access to the FS is not reserved to a dedicated resource. Between if(!theDir.exists()) and theDir.mkdir() the status could have changed, as well as it could change in bet...
What is the difference between a weak reference and an unowned reference?
...a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object).
But why two keywords? This distinction has to do with the fact that Optional types are built-in the Swift language. Long story short about them: optional types offer memory safety (this works ...
How can I avoid Java code in JSP files, using JSP 2?
...ance/composition.
Debuggability: if scriptlet throws an exception halfway, all you get is a blank page.
Testability: scriptlets are not unit-testable.
Maintainability: per saldo more time is needed to maintain mingled/cluttered/duplicated code logic.
Sun Oracle itself also recommends in the JSP co...
Git undo changes in some files [duplicate]
...ethod:
# revert, but do not commit yet
git revert -n <sha1>
# clean all the changes from the index
git reset
# now just add A
git add A
git commit
Another method again, requires the use of the rebase -i command. This one can be useful if you have more than one commit to edit:
# use rebase ...
Finding diff between current and last version
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I don't really understand the meaning of "last version".
As the previous commit can be accessed with HEAD^, I think that you are looking for something like:
git diff HEAD^ HEAD
As of Git 1.8.5, @ is an alias for HEAD, so you can us...
How do I find duplicate values in a table in Oracle?
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if you change < to != you will get all the records that duplicate. not just the 2nd or 3rd record
– moore1emu
Jan 4 '19 at 19:51
add a ...
How to disable copy/paste from/to EditText
...om context menus from appearing by.
edittext.setCustomSelectionActionModeCallback(new ActionMode.Callback() {
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return false;
}
public void onDestroyActionMode(ActionMode mode) { ...
Adaptive segue in storyboard Xcode 6. Is push deprecated?
...e. I am using Xcode 6 beta 2 and to test I used the single view template (calling the pre made view controller in IB ‘VC_A’). I then added another view controller (‘VC_B’). I then added a button on VC_A to show VC_B and another from VC_B back to VC_A. When I add a navigation controller as th...