大约有 11,642 项符合查询结果(耗时:0.0375秒) [XML]
Can someone explain this 'double negative' trick? [duplicate]
...single operand can be converted to true; otherwise, returns true.
So if getContext gives you a "falsey" value, the !! will make it return the boolean value false. Otherwise it will return true.
The "falsey" values are:
false
NaN
undefined
null
"" (empty string)
0
...
MySQL high CPU usage [closed]
...ication is running, if there's duplicate queries, how long they're taking, etc, etc. An example of something like this is one I've been working on called PHP Profiler but there are many out there. If you're using a piece of software like Drupal, Joomla or Wordpress you'll want to ask around within t...
How to secure MongoDB with username and password
...at starts with #auth=true in your mongod configuration file (default path /etc/mongo.conf). This will enable authentication for mongodb.
Then, restart mongodb : sudo service mongod restart
share
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...
C/C++ include header file order
...ers from other non-standard, non-system libraries (for example, Qt, Eigen, etc).
Headers from other "almost-standard" libraries (for example, Boost)
Standard C++ headers (for example, iostream, functional, etc.)
Standard C headers (for example, cstdint, dirent.h, etc.)
If any of the headers have a...
General guidelines to avoid memory leaks in C++ [closed]
...ption safety and resource disposal in C++, and no other pattern (sandwich, etc.) will give you both (and most of the time, it will give you none).
See below a comparison of RAII and non RAII code:
void doSandwich()
{
T * p = new T() ;
// do something with p
delete p ; // leak if the p pro...
How to list the contents of a package using YUM?
...
rpm -ql [packageName]
Example
# rpm -ql php-fpm
/etc/php-fpm.conf
/etc/php-fpm.d
/etc/php-fpm.d/www.conf
/etc/sysconfig/php-fpm
...
/run/php-fpm
/usr/lib/systemd/system/php-fpm.service
/usr/sbin/php-fpm
/usr/share/doc/php-fpm-5.6.0
/usr/share/man/man8/php-fpm.8.gz
...
/var/...
Include headers when using SELECT INTO OUTFILE?
...nd also matt's answer for a way to quickly get all the ColName1, ColName2, etc. Very useful add-ons to this great answer!
– Andrew T
Oct 5 '15 at 1:11
1
...
Get the IP address of the machine
...se strace ip r get 1.1.1.1 and follow the yellow brick road.
Set it with /etc/hosts
This is my recommendation if you want to stay in control
You can create an entry in /etc/hosts like
80.190.1.3 publicinterfaceip
Then you can use this alias publicinterfaceip to refer to your public interfa...
Would you, at present date, use JBoss or Glassfish (or another) as Java EE server for a new project?
...Do you have to use any of the other major J2EE technologies like JMS, ESB, etc? If so, and you really can't do without, then you are again constrained to a full-blown J2EE container. Carefully think and investigate before you commit to BPM, for example, and avoid AquaLogic BPM at (almost) all cost...
How to determine SSL cert expiration date from a PEM encoded certificate?
...s in order of their expiration, most recently expiring first.
for pem in /etc/ssl/certs/*.pem; do
printf '%s: %s\n' \
"$(date --date="$(openssl x509 -enddate -noout -in "$pem"|cut -d= -f 2)" --iso-8601)" \
"$pem"
done | sort
Sample output:
2015-12-16: /etc/ssl/certs/Staat_der_Ned...