I have a function call in a program that I'm maintaining has 28 arguments for a printf call. It's printing a lot of data in a CSV file. I have problems following finding where what goes and I have some mismatches in the parameters types. I enabled -Wall in gcc and I get warnings like: n.c:495: warning: int format, pointer arg (arg 15) n...
Hi all, I'd like to determine the environment's current codepage at runtime from a Unix shell script. What's the most reliable way of doing this? I'm looking into parsing environment variable $LC_ALL, but it isn't always set to a useful value, and its format seems to vary (can be <locale>, or <locale>.<code page>, or <locale>.<code pag...
NSLog function accepts printf format specifiers. My question is about %x specifier. Does this print hex codes as sequence on memory? Or does it have it's own printing sequence style? unsigned int a = 0x000000FF; NSLog(@"%x", a); Results of above code on little or big endian processors are equal or different? And how about NSString's -...
After learning that both strncmp is not what it seems to be and strlcpy not being available on my operating system (Linux), I figured I could try and write it myself. I found a quote from Ulrich Drepper, the libc maintainer, who posted an alternative to strlcpy using mempcpy. I don't have mempcpy either, but it's behaviour was easy to r...
Suppose we have the following method (it is in c code): const char *bitap_search(const char *text, const char *pattern) My question is how can I compare text and pattern if they are char? This method is like a substring problem but I am confused a bit can I write in term of char such code? if (text[i]==pattern[i])? look i am interesti...
Today I discovered alarming behavior when experimenting with bit fields. For the sake of discussion and simplicity, here's an example program: #include <stdio.h> struct Node { int a:16 __attribute__ ((packed)); int b:16 __attribute__ ((packed)); unsigned int c:27 __attribute__ ((packed)); unsigned int d:3 __attribute__ ((packe...
I am a beginning C programmer (though not a beginning programmer) looking to dive into a project to teach myself C. My project is music-based, and because of this I am curious whether there are any 'best practices' per-se, when it comes to timing functions. Just to clarify, my project is pretty much an attempt to build some barebones m...
I realize this might be a long shot, but does anyone have an example of using the EI-1050 probe with a Labjack controller in something C-related? I'm currently using a Labjack U12 if it matters. It installed 2 examples, ljsht and ljsht-multi, that seem to be doing something related to it, but I can't find the source code. Thank you for...
Lets say I have the following: CHARLINK * _init_link(CHARLINK **link) { short i; (*link)->cl = (CHARLINK **) calloc(NUM_CHARS, sizeof(CHARLINK *)); for (i = 0; i < NUM_CHARS; i++) (*link)->cl[i] = NULL; return (*link); } Is the loop to initialize each element to NULL necessary or are they automatically NULL ...
i want to know how can one know the functions present in header files in c when running in linux systems ...
I found this regarding how the C preprocessor should handle string literal concatenation (phase 6). However, I can not find anything regarding how this is handled in C++ (does C++ use the C preprocessor?). The reason I ask is that I have the following: const char * Foo::encoding = "\0" "1234567890\0abcdefg"; where encoding is a stati...
Oftentimes data structures' valid initialization is to set all members to zero. Even when programming in C++, one may need to interface with an external API for which this is the case. Is there any practical difference between: some_struct s; memset(&s, 0, sizeof(s)); and simply some_struct s = { 0 }; Do folks find themselves usi...
I need help with malloc() inside another function. I'm passing a pointer and size to the function from my main() and I would like to allocate memory for that pointer dynamically using malloc() from inside that called function, but what I see is that.... the memory, which is getting allocated, is for the pointer declared within my called...
I recently started a small personal project (RGB value to BGR value conversion program) in C, and I realised that a function that converts from RGB to BGR can not only perform the conversion but also the inversion. Obviously that means I don't really need two functions rgb2bgr and bgr2rgb. However, does it matter whether I use a functi...
For this code: #include<stdio.h> void hello() { printf("hello\n"); } void bye() { printf("bye\n"); } int main() { printf("%p\n", hello); printf("%p\n", bye); return 0; } output on my machine: 0x80483f4 0x8048408 [second address is bigger in value] on Codepad 0x8048541 0x8048511 [second address is smaller in v...
Both ideone.com and codepad.org have Little-Endian architechtures. I want to test my code on some machine with Big-Endian architechture (for example - Solaris - which I don't have). Is there some easy way that you know about? ...
I am building a shared library on Ubuntu 9.10. I want to export only a subset of my functions from the library. On the Windows platform, this would be done using a module definition (.def) file which would contain a list of the external and internal names of the functions exported from the library. I have the following questions: How ...
I have a server and a client written in C. I try to load a shared library in the server and then pass library function pointers to the client. This way I can change the library without have to compile the client. Because of every process has its own separate memory space, I wonder if it is possible to load a shared library on a shared m...
Or it's the same in c/c++? ...
It should give me the number of inputs entered by the user. But it gives 100. I compiled with gcc. #include <stdio.h> int arr[100]; int count=0; int max=100; int main(){ int i, input; printf("Enter integer values one by one, q to quit.\n"); for(i=0;i<max;i++){ scanf("%d",&input); arr[i]=input; if(input=='q')break; count++;...