WORDSIZE define in /usr/include/bits/wordsize.h by compiler. In my opinion, i think why does user space use double size for kernel space is that it is easy represented for major and minor dev number, and in kernel space 20 bit for major and 12 bit for minor. 2009/7/13 SandeepKsinha <sandeepksinha@xxxxxxxxx>: > > ail.com> wrote: >> >> FYI >> >> /usr/include/bits/types.h >> >> /* Fixed-size types, underlying types depend on word size and compiler. >> */ >> typedef signed char __int8_t; >> typedef unsigned char __uint8_t; >> typedef signed short int __int16_t; >> typedef unsigned short int __uint16_t; >> typedef signed int __int32_t; >> typedef unsigned int __uint32_t; >> #if __WORDSIZE == 64 >> typedef signed long int __int64_t; >> typedef unsigned long int __uint64_t; >> #elif defined __GLIBC_HAVE_LONG_LONG >> __extension__ typedef signed long long int __int64_t; >> __extension__ typedef unsigned long long int __uint64_t; >> #endif >> >> >> #if __WORDSIZE == 32 >> # define __SQUAD_TYPE __quad_t >> # define __UQUAD_TYPE __u_quad_t >> # define __SWORD_TYPE int >> # define __UWORD_TYPE unsigned int >> # define __SLONG32_TYPE long int >> # define __ULONG32_TYPE unsigned long int >> # define __S64_TYPE __quad_t >> # define __U64_TYPE __u_quad_t >> /* We want __extension__ before typedef's that use nonstandard base types >> such as `long long' in C89 mode. */ >> # define __STD_TYPE __extension__ typedef >> #elif __WORDSIZE == 64 >> # define __SQUAD_TYPE long int >> # define __UQUAD_TYPE unsigned long int >> # define __SWORD_TYPE long int >> # define __UWORD_TYPE unsigned long int >> # define __SLONG32_TYPE int >> > > Thats what I meant? I mean where can you see the size of dev_t to be mapping > to unsigned long. > Its 64 bit on both, with WORDSIZE ==32 and 64. > > > Regards, > Sandeep. > > > > > > > “To learn is to change. Education is a process that changes the learner.” > > -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
