CTASSERT(9) compile time assertion macro


In sys/param.h In sys/systm.h Fn CTASSERT expression


The Fn CTASSERT macro evaluates Fa expression at compile time and causes a compiler error if it is false.

The Fn CTASSERT macro is useful for asserting the size or alignment of important data structures and variables during compilation, which would otherwise cause the code to fail at run time.


The Fn CTASSERT macro should not be used in a header file. It is implemented using a dummy typedef, with a name (based on line number) that may conflict with a Fn CTASSERT in a source file including that header.


Assert that the size of the Vt uuid structure is 16 bytes.

"CTASSERT(sizeof(struct uuid) == 16);"


This manual page was written by An Hiten M. Pandya Aq [email protected] .