GENASSYM(1) BSD General Commands Manual GENASSYM(1)
NAME
genassym -- emit an assym.h file
SYNOPSIS
genassym [-c] [-f] C compiler invocation
DESCRIPTION
genassym is a shell script normally used during the kernel build process to create an assym.h file. This file defines a number of cpp con-
stants derived from the configuration information genassym reads from stdin. The generated file is used by kernel sources written in assem-
bler to gain access to information (e.g. structure offsets and sizes) normally only known to the C compiler.
Arguments to genassym are usually of the form ${CC} ${CFLAGS} ${CPPFLAGS} where ${CC} is the C compiler used to compile the kernel, while
${CFLAGS} and ${CPPFLAGS} are flag arguments to the C compiler. The script creates a C source file from its input. Then the C compiler is
called according to the script's arguments to compile this file.
Normally genassym instructs the C compiler to create an assembler source from the constructed C source. The resulting file is then processed
to extract the information needed to create the assym.h file. The -c flag instructs genassym to create slightly different code, generate an
executable from this code and run it. In both cases the assym.h file is written to stdout. The -f flag instructs genassym to create forth
code.
DIAGNOSTICS
Either self-explanatory, or generated by one of the programs called from the script.
SEE ALSO
genassym.cf(5)
HISTORY
The genassym command appeared in NetBSD 1.3 as ``genassym.sh'' in /usr/src/sys/kern. It became a userland utility in NetBSD 4.0.
BSD
April 13, 2010 BSD
