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default storage class specifier of a variable


I know java,but I am just beginner in C.I have some confusions
regarding extern storage specifier and default storage class specifier
for a variable when it has file scope that is ,when it is not
defined within
any block

--
Posted via http://dbforums.com
Nov 13 '05 #1
1 2517
On Sat, 05 Jul 2003 06:05:07 +0000, ravi_shankar
<me*********@db forums.com> wrote in comp.lang.c:

I know java,but I am just beginner in C.I have some confusions
regarding extern storage specifier and default storage class specifier
for a variable when it has file scope that is ,when it is not
defined within
any block


The "extern" keyword is not a storage specifier, although it has some
restrictions as to the storage duration of the objects with which it
can be used. The "extern" keyword specifies that an object or
function has external linkage, which means that it can be referred to
by name from translation units other than the one it was defined in.

As to storage duration, all objects defined at file scope have static
storage duration. They also have external linkage unless defined
specifically with the keyword "static", which gives them internal
linkage.

--
Jack Klein
Home: http://JK-Technology.Com
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Nov 13 '05 #2

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