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What is the difference between printf() and puts() in C?
...e (except for the added newline) if the string doesn't contain any control characters (%) but if you cannot rely on that (if mystr is a variable instead of a literal) you should not use it.
So, it's generally dangerous -and conceptually wrong- to pass a dynamic string as single argument of printf...
Maximum length for MySQL type text
...e to the max length of a text field in my MySQL database table. How many characters can a type text field store?
8 Answer...
How to compare dates in datetime fields in Postgresql?
... manipulation on the input string, correct? you don't need to be afraid:
SELECT *
FROM table
WHERE update_date >= '2013-05-03'::date
AND update_date < ('2013-05-03'::date + '1 day'::interval);
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What are the mechanics of short string optimization in libc++?
...th:
1 bit goes to the long/short flag.
7 bits goes to the size.
Assuming char, 1 byte goes to the trailing null (libc++ will always store a trailing null behind the data).
This leaves 3 words minus 2 bytes to store a short string (i.e. largest capacity() without an allocation).
On a 32 bit mach...
Passing variable arguments to another function that accepts a variable argument list
...#include <stdio.h>
template<typename... Args> void test(const char * f, Args... args) {
printf(f, args...);
}
int main()
{
int a = 2;
test("%s\n", "test");
test("%s %d %d %p\n", "second test", 2, a, &a);
}
At the very least, it works with g++.
...
Why does appending “” to a String save memory?
...s that substring() gives a window onto an existing String - or rather, the character array underlying the original String. Hence it will consume the same memory as the original String. This can be advantageous in some circumstances, but problematic if you want to get a substring and dispose of the o...
When is CRC more appropriate to use than MD5/SHA1?
... inappropriate CRC hashes are for hash tables. It also explains the actual characteristics of the algorithm. The study also includes evaluation of other hash algorithms and is a good reference to keep.
The relevant conclusion on CRC for hashes:
CRC32 was never intended for hash table use. There...
What differences, if any, between C++03 and C++11 can be detected at run-time?
...zeof(b);
}
Also, the fact that string literals do not anymore convert to char*
bool isCpp0xImpl(...) { return true; }
bool isCpp0xImpl(char*) { return false; }
bool isCpp0x() { return isCpp0xImpl(""); }
I don't know how likely you are to have this working on a real implementation though. One t...
The tilde operator in C
... operator. It inverts the bits of the operand.
For example, if you have:
char b = 0xF0; /* Bits are 11110000 */
char c = ~b; /* Bits are 00001111 */
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How to know what the 'errno' means?
... threads. MT, in MT-Safe, stands for Multi Thread. -p26, The GNU C Library char * strerror(int errnum ) [Function] Preliminary: | MT-Unsafe race:strerror | AS-Unsafe heap i18n | AC-Unsafe mem | See Section 1.2.2.1 [POSIX Safety Concepts], page 2. -p58, The GNU C Library
– user...