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#ifndef UUID_h
#define UUID_h

#include <wtf/text/WTFString.h>

namespace WebCore {

// Creates a UUID that consists of 32 hexadecimal digits and returns its canonical form.
// The canonical form is displayed in 5 groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters.
// The hexadecimal values "a" through "f" are output as lower case characters.
//
// Note: for security reason, we should always generate version 4 UUID that use a scheme relying only on random numbers.
// This algorithm sets the version number as well as two reserved bits. All other bits are set using a random or pseudorandom
// data source. Version 4 UUIDs have the form xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx with hexadecimal digits for x and one of 8,
// 9, A, or B for y.
//
// On Windows, version 4 UUIDs are used since Windows 2000 (http://msdn.microsoft.com/en-us/library/aa446557.aspx).
// On MacOSX, version 4 UUIDs are used since Tiger (http://developer.apple.com/mac/library/technotes/tn/tn1103.html#TNTAG8).
// On Linux, the kernel offers the procfs pseudo-file /proc/sys/kernel/random/uuid that yields version 4 UUIDs (http://hbfs.wordpress.com/2008/09/30/ueid-unique-enough-ids/).
WEBCORE_EXPORT String createCanonicalUUIDString();

}

#endif
