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We initialize octal by putting 0 as prefix and hexadecimal as 0x. How can we initialize an int variable in binary number? Is there any access specifier in C for binary number? e.g %o for octal and %x for hexadecimal number.

Harsh
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  • [Can I use a binary literal in C or C++?](http://stackoverflow.com/questions/2611764/can-i-use-a-binary-literal-in-c-or-c) and [Is there a printf converter to print in binary format?](http://stackoverflow.com/questions/111928/is-there-a-printf-converter-to-print-in-binary-format) and [Binary constants using the ‘0b’ prefix](http://gcc.gnu.org/onlinedocs/gcc/Binary-constants.html) for more info. – Dayal rai Sep 03 '13 at 13:21

2 Answers2

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Recent versions of GCC provide an extension to the C standard. Use 0b or 0B to prefix a bit series like: 

int i = 0b0101010;
alk
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  • I use gcc version 4.7.2. Both 0b and 0B works. But what is the access specifier to print binary number? – Harsh Sep 03 '13 at 13:51
  • @Harsh: As far as I know there is none. However gcc overs you the possibility to roll your own: http://www.gnu.org/software/libc/manual/html_node/Customizing-Printf.html#Customizing-Printf – alk Sep 03 '13 at 13:55
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int a = 0b0001010; for GCC extension

P0W
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