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Coding Practices which enable the compiler/optimizer to make a faster program
...ns" and variable sections. Think of mail-merge.
Declare constant text (string literals) as static const
When variables are declared without the static, some compilers may allocate space on the stack and copy the data from ROM. These are two unnecessary operations. This can be fixed by using t...
How can I read and parse CSV files in C++?
...e (OK 14 ->But its only 15 to read the whole file).
std::vector<std::string> getNextLineAndSplitIntoTokens(std::istream& str)
{
std::vector<std::string> result;
std::string line;
std::getline(str,line);
std::stringstream lineStream(line);...
How to assign a Git SHA1's to a file without Git?
...having Git installed. Note that "\0" is the NULL-byte, not a two-character string.
For example, the hash of an empty file:
sha1("blob 0\0") = "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
$ touch empty
$ git hash-object empty
e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
Another example:
sha1("blob 7\...
Regular expressions in C: examples?
...egular expression library isn't too difficult to crash given certain input strings and certain regular expressions that "almost" match or involve a lot of special characters
– bdk
Jul 6 '09 at 2:16
...
Realistic usage of the C99 'restrict' keyword?
...ons could be saved, as mentioned by supercat.
Consider for example:
void f(char *restrict p1, char *restrict p2) {
for (int i = 0; i < 50; i++) {
p1[i] = 4;
p2[i] = 9;
}
}
Because of restrict, a smart compiler (or human), could optimize that to:
memset(p1, 4, 50);
memset(...
Unresolved external symbol on static class members
...ou must add the definitions to match your declarations of X and Y
unsigned char test::X;
unsigned char test::Y;
somewhere. You might want to also initialize a static member
unsigned char test::X = 4;
and again, you do that in the definition (usually in a CXX file) not in the declaration (which is...
C libcurl get output into a string
...URLOPT_WRITEDATA, p)
Here's a snippet of code that passes a buffer struct string {*ptr; len} to the callback function and grows that buffer on each call using realloc().
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>
struct string {
cha...
Splitting String with delimiter
I am currently trying to split a string 1128-2 so that I can have two separate values. For example, value1: 1128 and value2: 2, so that I can then use each value separately. I have tried split() but with no success. Is there a specific way Grails handles this, or a better way of doing it?
...
Program only crashes as release build — how to debug?
... was indeed caused by a buffer overflow, caused a single byte difference:
char *end = static_cast<char*>(attr->data) + attr->dataSize;
This is a fencepost error (off-by-one error) and was fixed by:
char *end = static_cast<char*>(attr->data) + attr->dataSize - 1;
The wei...
How can I truncate a datetime in SQL Server?
...11), getdate(), 113) as datetime)
The wrong way works by converting to a string, truncating the string, and converting back to a datetime. It's wrong, for two reasons: 1)it might not work across all locales and 2) it's about the slowest possible way to do this... and not just a little; it's like ...