Length of various data types in the C language

On 32-bit platforms and 64-bit platforms, the same data type may have different data lengths:

Type	32-bit Platform	64-bit Platform
Char	1	1
Short	2	2
Int	4	4
Long	4	8
Long Long	8	8
Float	4	4
Double	8	8
size_t	4	8
ssize_t	4	8

See, No,

You can see the difference from the above results, so don't assume the data length of the color background row in the table above, because it will change.

Because the functions of the system return these values, you must know their size and make the appropriate error-proof conversion. In other cases, you need to fix the data length data type across different platforms, and you can use some fixed-length data types, which will not be confusing, like this:

int8_t int16_t int32_t int64_t

uint8_t uint16_t uint32_t uint64_t

Length of various data types in the C language