Linked Questions

On a cross platform c/c++ project (Win32, Linux, OSX), I need to use the *printf functions to print some variables of type size_t. In some environments size_t's are 8 bytes and on others they are 4. ...

I read that the size of a struct is at least the sum of individual fields inside it, and it can be greater than that when using struct array for alignment. What is alignment, why does it add that so ...

C and C++ have many differences, and not all valid C code is valid C++ code. (By "valid" I mean standard code with defined behavior, i.e. not implementation-specific/undefined/etc.) Is there any ...

I have a variable of type size_t, and I want to print it using printf(). What format specifier do I use to print it portably? In 32-bit machine, %u seems right. I compiled with g++ -g -W -Wall -...

The following code receives seg fault on line 2: char *str = "string"; str[0] = 'z'; // could be also written as *str = 'z' printf("%s\n", str); While this works perfectly well: char str[] = "...

I was wondering if someone could explain to me what the #pragma pack preprocessor statement does, and more importantly, why one would want to use it. I checked out the MSDN page, which offered some ...

I'm trying to print types like off_t and size_t. What is the correct placeholder for printf() that is portable? Or is there a completely different way to print those variables?

I want to print out a variable of type size_t in C but it appears that size_t is aliased to different variable types on different architectures. For example, on one machine (64-bit) the following code ...

printf("%lu \n", sizeof(*"327")); I always thought that size of a pointer was 8 bytes on a 64 bit system but this call keeps returning 1. Can someone provide an explanation?

I am working with structs in c on linux. I started using bit fields and the "packed" attribute and I came across a wierd behavior: struct __attribute__((packed)) { int a:12; int b:32;...

I ran the following program on my computer (64-bit Intel running Linux). #include <stdio.h> void test(int argc, char **argv) { printf("[test] Argc Pointer: %p\n", &argc); printf("[...

Can you think of 'a program' which gives 'different outputs for a C and a C++ compilers' (yet gives consistent output under the same language)?

I am trying to compile the below on RHEL 5.6 , 64 bit, and i keep getting a warning "var.c:7: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long unsigned int’" Here is my ...

By man I find printf("%*d", width, num); and printf("%2$*1$d", width, num); are equivalent. But IMO the second style should be the same as: printf("%*...

I have been advised to use the following options with GCC, as it helps to avoid a lot of common errors. It turns on a bunch of warnings and -Werror turns them into errors. gcc -pedantic -W -Wall -...