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Why 0 is true but false is 1 in the shell?
...it code of 0 (the result of /bin/true). Otherwise they evaluate as false.
Strings are evaluated differently than exit codes:
if [ 0 ] ; then echo not null ; fi
if [ $(echo 0) ] ; then echo not null ; fi
if [ -z "" ] ; then echo null ; fi
The (( )) arithmetic operator interprets 1 and 0 as true ...
Stack smashing detected
...s protection variables (called canaries) which have known values. An input string of size greater than 10 causes corruption of this variable resulting in SIGABRT to terminate the program.
To get some insight, you can try disabling this protection of gcc using option -fno-stack-protector while co...
How to know what the 'errno' means?
...
You can use strerror() to get a human-readable string for the error number. This is the same string printed by perror() but it's useful if you're formatting the error message for something other than standard error output.
For example:
#include <errno.h>
#include ...
Should I call Close() or Dispose() for stream objects?
...Microsoft.Usage : Object 'f' can be disposed more than once in method 'Foo(string)'. To avoid generating a System.ObjectDisposedException you should not call Dispose more than one time on an object.: Lines: 41" So while the current implementation is fine with calling Close and Dispose, according to ...
Check if a class has a member function of a given signature
...value = type::value;
};
Usage:
struct X {
int serialize(const std::string&) { return 42; }
};
struct Y : X {};
std::cout << has_serialize<Y, int(const std::string&)>::value; // will print 1
sh...
How to convert std::string to lower case?
I want to convert a std::string to lowercase. I am aware of the function tolower() , however in the past I have had issues with this function and it is hardly ideal anyway as use with a std::string would require iterating over each character.
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From Arraylist to Array
...le to convert from ArrayList to Array?
I have a text file with each line a string:
9 Answers
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Why declare a struct that only contains an array in C?
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You can use struct to make a new type of data like string. you can define :
struct String {
char Char[MAX];
};
or you can create a List of data that you can use it by argument of functions or return it in your methods. The struct is more flexible than an array, because...
What does the explicit keyword mean?
...cidental construction that can hide bugs.
Contrived example:
You have a MyString(int size) class with a constructor that constructs a string of the given size. You have a function print(const MyString&), and you call print(3) (when you actually intended to call print("3")). You expect it to p...
How do I URL encode a string
I have a URL string ( NSString ) with spaces and & characters. How do I url encode the entire string (including the & ampersand character and spaces)?
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