c99

In the following rules for the case when array decays to pointer: An lvalue [see question 2.5] of type array-of-T which appears in an expression decays (with three exceptions) into a pointer to its first element; the type of the resultant pointer is pointer-to-T. (The exceptions are when the array is the operand of a sizeof or & operator, or is a literal string initializer for a character array.) How to understand the case when the array is "literal string initializer for a character array"? Some example please. Thanks! Prasoon Saurav The three exceptions where an array does not decay into a

Following an hot comment thread in another question, I came to debate of what is and what is not defined in C99 standard about C arrays. Basically when I define a 2D array like int a[5][5] , does the standard C99 garantee or not that it will be a contiguous block of ints, can I cast it to (int *)a and be sure I will have a valid 1D array of 25 ints. As I understand the standard the above property is implicit in the sizeof definition and in pointer arithmetic, but others seems to disagree and says casting to (int*) the above structure give an undefined behavior (even if they agree that all

I was wondering if there were any files in which I could set the -std=c99 flag, so that I would not have to set it for every compilation. I am using GCC 4.4 on Ubuntu. Instead of calling /usr/bin/gcc , use /usr/bin/c99 . This is the Single-Unix-approved way of invoking a C99 compiler. On an Ubuntu system, this points to a script which invokes gcc after having added the -std=c99 flag, which is precisely what you want. How about alias gcc99= gcc -std=c99 ? 来源： https://stackoverflow.com/questions/2193634/setting-std-c99-flag-in-gcc

I learned today that there are digraphs in C99 and C++. The following is a valid program: %:include <stdio.h> %:ifndef BUFSIZE %:define BUFSIZE 512 %:endif void copy(char d<::>, const char s<::>, int len) <% while (len-- >= 0) <% d<:len:> = s<:len:>; %> %> My question is: why do they exist? Digraphs were created for programmers that didn't have a keyboard which supported the ISO 646 character set. http://en.wikipedia.org/wiki/C_trigraph I believe that their existence can be traced back to the possibility that somewhere, somebody is using a compiler with an operating system whose character set