In the C language, the number of bytes for a double, long, unsigned, int, char type data

In the C language, the number of bytes for a double, long, unsigned, int, char type data

http://blog.csdn.net/lyl0625/article/details/7350045

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I can't remember, put it down:

is related to the machine word length and compiler:

Therefore, the width of the int,long int,short int may vary depending on the compiler. But there are several ironclad principles (Ansi/iso):

1 sizeof (short int) <=sizeof (int.) 2 sizeof (int) <=sizeof (long int) 3 short int should be at least 16 bits (2 bytes) 4 long int should be at least 32 bits.

Unsigned is an unsigned meaning.

For example:
16-bit compilers

Char:1 byte char* (i.e. pointer variable): 2 bytes short int:2 bytes int:2 bytes unsigned int:2 bytes float:4 bytes double:8 bytes long:4 bytes long long:8 bytes UN Signed Long:4 bytes

32-bit compiler (see here, compared with 16-bit machine, 64-bit machine, bold type is different, the rest is the same)

Char:1 bytes char*(that is, pointer variables): 4 bytes (32-bit addressing space is 2^32, which is 32 bit, or 4 bytes. The same 64-bit compiler) (16-bit machine, 32-bit machine, 64-bit machine are different)
Short int:2 byte int: 4 bytes (16-bit machine is 2b,32 bit &64 bit is 4B)int : 4 bytes (16-bit machine is 2b,32 bit &64 bit is 4B)
Float:4 bytes of Double:8 bytes
Long: 4 bytes (16 bit &32 bit is 4b,64 bit is 8B) long long:8 bytes  Long: 4 bytes (16&32 bit is 4b,64 bit is 8B)

64-bit compilers

Char:1 byte char* (i.e. pointer variable): 8 bytes Short int:2 bytes Int:4 bytes unsigned int:4 bytes float:4 bytes double:8 bytes long:8 bytes long long:8 bytes UN Signed Long:8 bytes

In the C language, the number of bytes for a double, long, unsigned, int, char type data