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How to permanently set $PATH on Linux/Unix? [closed]
... session. In case of the shell script you must use a specific shell syntax and export or set commands.
System wide
/etc/environment List of unique assignments, allows references. Perfect for adding system-wide directories like /usr/local/something/bin to PATH variable or defining JAVA_HOME. Used ...
live output from subprocess command
..., I use subprocess.Popen to run the code, collect the output from stdout and stderr into a subprocess.PIPE --- then I can print (and save to a log-file) the output information, and check for any errors. The problem is, I have no idea how the code is progressing. If I run it directly from the c...
delete vs delete[] operators in C++
What is the difference between delete and delete[] operators in C++?
7 Answers
7
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What is thread safe or non-thread safe in PHP?
...ncy approaches:
Different web servers implement different techniques for handling incoming HTTP requests in parallel. A pretty popular technique is using threads -- that is, the web server will create/dedicate a single thread for each incoming request. The Apache HTTP web server supports multiple m...
Where in memory are my variables stored in C?
...sidering that the memory is divided into four segments: data, heap, stack, and code, where do global variables, static variables, constant data types, local variables (defined and declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc...
What makes Lisp macros so special?
...not had the privilege of using Lisp macros. As someone who wants to understand the buzz, please explain what makes this feature so powerful.
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CSS Selector “(A or B) and C”?
...(.a .b) .c {
/* stuff goes here */
}
You can find more info on it here and here. Currently, most browsers support its initial version :any(), which works the same way, but will be replaced by :matches(). We just have to wait a little more before using this everywhere (I surely will).
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NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
I have an application that deals with clients from all over the world, and, naturally, I want everything going into my databases to be UTF-8 encoded.
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What are the main performance differences between varchar and nvarchar SQL Server data types?
... most applications. However, if you need to support double-byte languages and you only have single-byte support in your database schema it's really expensive to go back and modify throughout your application.
The cost of migrating one application from varchar to nvarchar will be much more than t...