I have a string(char*), and i need to find its underlying datatype such as int, float, double, short, long, or just a character array containing alphabets with or with out digits(like varchar in SQL). For ex: char* str1 = "12312" char* str2 = "231.342" char* str3 = "234234243234" char* str4 = "4323434.2432342" char*...
Assuming Visual C/C++ 6, I have a complex data structure of 22399 elements that looks like this: { { "(SAME", "AS", "U+4E18)", "HILLOCK", "OR", "MOUND"}, { "TO", "LICK;", {1, 1, 0}, "TASTE,", "A", "MAT,", "BAMBOO", "BARK"}, { "(J)", "NON-STANDARD", "FORM", "OF", "U+559C", ",", {1, 1, 0}, "LIKE,", "LOVE,", "ENJOY;", {1, 1, 4}, "JOYFUL", ...
I was wondering if there was any difference in the way the following code was compiled into assembly. I've heard that switch-case is more efficient than if else, but in this example I am not quite sure if that would be the case. if(x==1){ ... }else if(x==2){ ... }else{ ... } and switch(x){ case 1: ... break; case 2: ... break;...
What is the basic differences between Semaphores & Spinlock? & In what best situations or conditions, we can use these. ...
For example, how to avoid writing the 'func_name' twice? #ifndef TEST_FUN # define TEST_FUN func_name # define TEST_FUN_NAME "func_name" #endif I'd like to follow the Single Point of Truth rule. Version of C preprocessor: $ cpp --version cpp (GCC) 4.1.2 20070626 (Red Hat 4.1.2-14) ...
I'm working on a project in C and it requires memalign(). Really, posix_memalign() would do as well, but darwin/OSX lacks both of them. What is a good solution to shoehorn-in memalign? I don't understand the licensing for posix-C code if I were to rip off memalign.c and put it in my project- I don't want any viral-type licensing LGPL-i...
I need a cross-platform editor control to use as GUI-part in an in-house tool. The control may be commercial, but with reasonable price. Required features: Platforms: Win32, OS X, Linux UTF-8 support Fine-grained run-time control to the text style (or at least color) Nice low-level plain C API without usual horrible bloat Should not p...
I am looking to create symlinks (soft links) from Java on a Windows Vista/ 2008 machine. I'm happy with the idea that I need to call out to the JNI to do this. I am after help on the actual C code though. What is the appropriate system call to create the link? Pointers to some good documentation on this subject would be very much appreci...
As I've mentioned before, I'm going through K&R, and overall am doing all right with it. However, in chapter 2, the section on bitwise operators (section 2.9), I'm having trouble understanding how one of the sample methods works -- and as a result, I'm having trouble with the associated exercises. (This isn't a dupe of my prior questio...
I'm working with embedded C for the first time. Although my C is rusty, I can read the code but I don't really have a grasp on why certain lines are the way the are. For example, I want to know if a variable is true or false and send it back to another application. Rather than setting the variable to 1 or 0, the original implementor chos...
I was trying to understand something with pointers, so I wrote this code: #include <stdio.h> int main(void) { char s[] = "asd"; char **p = &s; printf("The value of s is: %p\n", s); printf("The direction of s is: %p\n", &s); printf("The value of p is: %p\n", p); printf("The direction of p is: %p\n", &p); p...
How do you reverse a string in C or C++ without requiring a separate buffer to hold the reversed string? ...
I have a fairly simple const struct in some C code that simply holds a few pointers and would like to initialize it statically if possible. Can I and, if so, how? ...
I'm in need of a lightweight library for 2d & 3d vectors and 3x3 & 4x4 matrices. In basic C. Just so I don't reinvent the wheel suboptimally. Any suggestions? ...
I was writing a program in C++ to find all solutions of a^b = c (a to the power of b), where a, b and c together use all the digits 0-9 exactly once. The program looped over values of a and b, and ran a digit-counting routine each time on a, b and a^b to check if the digits condition was satisfied. However, spurious solutions can be gen...
How would I print a spinning curser in a utility that runs in a terminal using standard C? I'm looking for something that prints: \ | / - over and over in the same position on the screen? Thanks ...
I have a C++ library that provides various classes for managing data. I have the source code for the library. I want to extend the C++ API to support C function calls so that the library can be used with C code and C++ code at the same time. I'm using GNU tool chain (gcc, glibc, etc), so language and architecture support are not an is...
C++ is mostly a superset of C, but not always. In particular, while enumeration values in both C and C++ implicitly convert into int, the reverse isn't true: only in C do ints convert back into enumeration values. Thus, bitflags defined via enumeration declarations don't work correctly. Hence, this is OK in C, but not in C++: typedef en...
How would you go about converting a reasonably large (>300K), fairly mature C codebase to C++? The kind of C I have in mind is split into files roughly corresponding to modules (i.e. less granular than a typical OO class-based decomposition), using internal linkage in lieu private functions and data, and external linkage for public func...
Is there a standard way to see how much stack space your app has and what the highest watermark for stack usage is during a run? Also in the dreaded case of actual overflow what happens? Does it crash, trigger an exception or signal? Is there a standard or is it different on all systems and compilers? I'm looking specifically for Win...