November 2002
Beginner to intermediate
142 pages
4h 19m
English
Content preview from C Pocket Reference
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Identifiers
Identifiers are names of variables, functions, macros, types, etc. Identifiers are subject to the following formative rules:
An identifier consists of a sequence of letters (
AtoZ,atoz), digits (0to9), and underscores (_).The first character of an identifier must not be a digit.
Identifiers are case-sensitive.
There is no restriction on the length of an identifier. However, only the first 31 characters are generally significant.
Keywords are reserved and must not be used as identifiers. Following is a list of keywords:
auto |
enum |
restrict(*) |
unsigned |
break |
extern |
return |
void |
case |
float |
short |
volatile |
char |
for |
signed |
while |
const |
goto |
sizeof |
_Bool(*) |
continue |
if |
static |
_Complex(*) |
default |
inline(*) |
struct |
_Imaginary(*) |
do |
int |
switch | |
double |
long |
typedef | |
else |
register |
union |
External names —that is, identifiers of externally linked functions and variables—may be subject to other restrictions, depending on the linker: in portable C programs, external names should be chosen so that only the first eight characters are significant, even if the linker is not case-sensitive.
Some examples of identifiers are:
Valid: a, DM, dm, FLOAT, _var1, topOfWindow
|
Invalid: do, 586_cpu, zähler, nl-flag, US_$
|
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.