Those integer types are all defined in stdint.h
If you are using C99 just include stdint.h
. BTW, the 64bit types are there iff the processor supports them.
The questioner actually asked about int16 (etc) rather than (ugly) int16_t (etc).
There are no standard headers - nor any in Linux's /usr/include/ folder that define them without the "_t".
Source: Stackoverflow.com