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Is there a bash command which counts files?
...gt;/dev/null redirects stderr so that if there are 0 log files, ignore the error message. (Note that shopt -s nullglob would cause ls to list the entire working directory instead.)
wc -l consumes the directory listing as it's being generated, so the output of ls is never in memory at any point in ti...
Why doesn't list have safe “get” method like dictionary?
...f your list).
Of course, you can easily implement this yourself:
def safe_list_get (l, idx, default):
try:
return l[idx]
except IndexError:
return default
You could even monkeypatch it onto the __builtins__.list constructor in __main__, but that would be a less pervasive change since...
What does enumerate() mean?
What does for row_number, row in enumerate(cursor): do in Python?
5 Answers
5
...
How can I find the version of the Fedora I use?
...s... :-(
– BRPocock
Dec 2 '11 at 16:05
8
That's a wrong answer. The answer of @BruceONeel should ...
iPad keyboard will not dismiss if modal ViewController presentation style is UIModalPresentationForm
... UIViewController and call it when you want the keyboard gone:
@interface _TempUIVC : UIViewController
@end
@implementation _TempUIVC
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return YES;
}
@end
@implementation UIViewController (Helpers)
- ...
OS X Bash, 'watch' command
...directly.
– Oliver
Aug 25 '13 at 10:05
9
...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用 - C/C+...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4，该符号在函数 _main 中被引用1>NetClient.obj : error L...1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@...
List of lists changes reflected across sublists unexpectedly
...at you create a new list at each position. One way to do it is
[[1]*4 for _ in range(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's beca...
Converting an int to a binary string representation in Java?
...
answered Jul 30 '15 at 3:05
AbbyPadenAbbyPaden
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...
How do you sign a Certificate Signing Request with your Certification Authority?
...ivate key:
Sign the certificate? [y/n]:Y
failed to update database
TXT_DB error number 2
So unique_subject = no is perfect for testing.
If you want to ensure the Organizational Name is consistent between self-signed CAs, Subordinate CA and End-Entity certificates, then add the following to you...