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File being used by another process after using File.Create()
I'm trying to detect if a file exists at runtime, if not, create it. However I'm getting this error when I try to write to it:
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How to remove the lines which appear on file B from another file A?
I have a large file A (consisting of emails), one line for each mail. I also have another file B that contains another set of mails.
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Are class names in CSS selectors case sensitive?
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CSS selectors are generally case-insensitive; this includes class and ID selectors.
But HTML class names are case-sensitive (see the attribute definition), and that's causing a mismatch in your second example. This has not changed in HTML5.1
This is because the case-sensitivity of selectors i...
Delete all files in directory (but not directory) - one liner solution
I want to delete all files inside ABC directory.
11 Answers
11
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Significance of -pthread flag when compiling
...ook for anything that starts with %{pthread:.
On my computer, this causes files to be compiled with -D_REENTRANT, and linked with -lpthread. On other platforms, this could differ. Use -pthread for most portability.
Using _REENTRANT, on GNU libc, changes the way some libc headers work. As a specifi...
Mongoose, Select a specific field with find
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The _id field is always present unless you explicitly exclude it. Do so using the - syntax:
exports.someValue = function(req, res, next) {
//query with mongoose
var query = dbSchemas.SomeValue.find({}).select('name -_id')...
ViewParam vs @ManagedProperty(value = “#{param.id}”)
...ditional <f:event type="preRenderView" listener="#{bean.init}" /> inside the <f:metadata> to do initialization/preloading based on the set values. Since JSF 2.2 you could use <f:viewAction> for that instead.
Allows for nested <f:converter> and <f:validator> for more fi...
Find the index of a dict within a list, by matching the dict's value
... name (using a dictionary), this way get operations would be O(1) time. An idea:
def build_dict(seq, key):
return dict((d[key], dict(d, index=index)) for (index, d) in enumerate(seq))
info_by_name = build_dict(lst, key="name")
tom_info = info_by_name.get("Tom")
# {'index': 1, 'id': '2345', 'na...
How to store arrays in MySQL?
...ables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
);
CREATE TABLE person_fruit (
`person_id` INT NOT NULL,
`fruit_name`...
How do I update an entity using spring-data-jpa?
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Identity of entities is defined by their primary keys. Since firstname and lastname are not parts of the primary key, you cannot tell JPA to treat Users with the same firstnames and lastnames as equal if they have different u...