print something without semi colon
Possible Duplicate: Hello world in C with no semi-colons? how to print something in c/c++ without having semi colon in programme ...
c
including tk.h and tcl.h in c program
hi, i am working on an ubuntu system. My aim is to basically make an IDE in C language using GUI tools from TCL/TK. I installed tcl 8.4, tk8.4, tcl8.4-dev, tk8.4-dev and have the tk.h and tcl.h headers file in my system. But, when I am running a basic hello world program it's showing a hell lot of errors. #include "tk.h" #include "stdio...
Why is this C or C++ macro not expanded by the preprocessor?
Can someone points me the problem in the code when compiled with gcc 4.1.0. #define X 10 int main() { double a = 1e-X; return 0; } I am getting error:Exponent has no digits. When i replace X with 10, it works fine. Also i checked with g++ -E command to see the file with preprocessors applied, it has not replaced X with 10. I was ...
Explicit initialization of struct/class members
struct some_struct{ int a; }; some_struct n = {}; n.a will be 0 after this; I know this braces form of initialization is inherited from C and is supported for compatibility with C programs, but this only compiles with C++, not with the C compiler. I'm using Visual C++ 2005. In C this type of initialization struct some_struct n =...
Is there a good way to copy a Gtk widget?
Is there a way, using the Gtk library in C, to clone a Gtk button (for instance), and pack it somewhere else in the app. I know you can't pack the same widget twice. And that this code obviously wouldn't work, but shows what happens when I attempt a shallow copy of the button: GtkButton *a = g_object_new(GTK_TYPE_BUTTON, "label", "o_0",...
[gtk+] error: undeclared function
Hello, In my gtk+ application i have function in mainwin.c: void on_prev( GtkWidget* btn, MainWin* mw ) { ... } And in file ui.h i have: #include "mainwin.h" static const GtkActionEntry entries[] = { { "Go Back", GTK_STOCK_GO_BACK, "Go Back", "<control>b", "Go Back", G_CALLBACK(on_prev) ...
Division by zero: Undefined Behavior or Implementation Defined in C and/or C++ ?
Regarding division by zero, the standards say: C99 6.5.5p5 - The result of the / operator is the quotient from the division of the first operand by the second; the result of the % operator is the remainder. In both operations, if the value of the second operand is zero, the behavior is undefined. C++03 5.6.4 - The binary / opera...
Getting plane slices from array data
Greetings all, I read 3d grid data (from multiple TIF images) into a structure as follows : typedef struct VolumeData{ int nx; int ny; int nz; unsigned char *data; // size is nx*ny*nz } Now I want to get the plane slices from this 1-D grid data: eg: unsigned char* getXYPlaneStack(VolumeData *vol,int z); I could implement ab...
Why does Apple use Objective-C for iPhone development? (App Store)
I'm interested to know your opinion on why Apple uses a language such as Objective-C for app development. Does Apple's app store allow apps written only in this language? Does apple even look at your source-code or does it just care of the binary output? I learned that most of their app rejection (in the app store) is based upon apps cr...
Two method for linking a object using GCC ?
I've known that I should use -l option for liking objects using GCC. that is gcc -o test test.c -L./ -lmy But I found that "gcc -o test2 test.c libmy.so" is working, too. When I use readelf for those two executable I can't find any difference. Then why people use -l option for linking objects? Does it have any advantage? ...
Getting value of LSB from Hex (C code)
Hi - first post here :) I've got a code like this in C: unsigned char const data[ ] = {0x0a, 0x1d, 0xf0, 0x07}; I need to extract it such that the final value is: 0xa1df7 I have only been able to extract and get it working if the hex values that have at least 1 zero: unsigned char const data[ ] = {0x0a, 0xd0, 0xf0, 0x07}; using...
sqlite tutorial
Is there any good tutorials/books on how to use sqlite with C?? ...
What time function do I need to use with pthread_cond_timedwait?
The pthread_cond_timedwait function needs an absolute time in a time timespec structure. What time function I'm suppose to use to obtain the absolute time. I saw a lot of example on the web and I found almost all time function used. (ftime, clock, gettimeofday, clock_gettime (with all possible CLOCK_...). The pthread_cond_timedwait use...
The C vs. C++ way
Hi, So I have to write a program that will iterate through an image and record the pixel locations corresponding to each color pixel that appears in it. For example, given http://www.socuteurl.com/fishywishykissy I need to find the coordinates of all yellow, purple, dark pink, etc pixels. In C++ I would use a hash table to do this...
How to optimize this simple function which translates input bits into words?
I have written a function which reads an input buffer of bytes and produces an output buffer of words where every word can be either 0x0081 for each ON bit of the input buffer or 0x007F for each OFF bit. The length of the input buffer is given. Both arrays have enough physical place. I also have about 2Kbyte free RAM which I can use for ...
When to pass by value?
Dear all. I was wondering if there are examples of situations where you would purposefully pass an argument by value in C. Let me rephrase. When do you purposefully use C's pass-by-value for large objects? Or, when do you care that the object argument is fully copied in a local variable? EDIT: Now that I think about it, if you can avoid...
How to update old C code?
I have been working on some 10 year old C code at my job this week, and after implementing a few changes, I went to the boss and asked if he needed anything else done. That's when he dropped the bomb. My next task was to go through the 7000 or so lines and understand more of the code, and to modularize the code somewhat. I asked him how...
Sleep command in tabbar based application is not working properly
HI , i am working on a tab bar navigation based application. once the application loaded i am loading a RSS feed content from a site in its first tab. I am using autoreleasepol to load the RSS feed inside the view controller and i have the sleeping time as 2 seconds, but the initial loading screen taking more anywhere between 3 to 7 se...
GCC / C++ Static linking for headers in a shared object
-I am trying to create a shared object libfoo.so. libfoo.so is created from "foo.c" - Assume that I include headers "static.h" and "Dynamic.h" where in I want the compiler to resolve the symbols for Static.h and leave the rest ie from Dynamic.h for runtime. - How do i do this ? What are the CFLAG and LDFLAG options that I need to pas...
Learning C, would appreciate input on why this solution works.
This is literally the first thing I've ever written in C, so please feel free to point out all it's flaws. :) My issue, however is this: if I write the program the way I feel is cleanest, I get a broken program: #include <sys/queue.h> #include <stdlib.h> #include <stdio.h> #include <string.h> /* Removed prototypes and non related cod...