Here are some practice that will hopefully make you feel more comfortable and more productive when you poking around with os161 syscalls.
Tired of bmake & bmake install every time?
Edit $OS161_SRC/mk/os161.kernel.mk, find this line:
all: includelinks .WAIT $(KERNEL)
Add some lines below it:
all: includelinks .WAIT $(KERNEL)
#generate tags for ctags, excluding some directories
cd $(TOP);ctags -R --exclude='.git' --exclude='build' --exclude='kern/compile' .; cd-
#automatically execute bmake install after bmake
bmake install
Then a single bmake will automatically generate tags for your source file as
well as install the executable.
Work on file system calls first
Work on file system calls and make them work correctly first, since user level
I/O functions (most importantly printf) rely heavily on sys_write and
sys_read of console. If you first work on the process system calls, how would
you assure your code is right? Without a working and correct printf, most of
the test programs won't work.
Test your code
Test programs in $OS161_SRC/user/testbin are very helpful when you want
to test your code, especially badcall(asst2), filetest, crash (for
kill_curthread), argtest (for execv) and forktest.
You can use the p command provided by os161 kernel menu to execute this test
programs:
OS/161 kernel [? for menu]: p /testbin/argtest abc def ghi jkl mno p
Use GDB
Without GDB, you're dead. It's really worth spending some time to learn the
basic usage of gdb. An upset fact is that you can not watch user level code (or
you don't want to bother), so use the "printf debug method" in user code.
Here are a few excellent gdb tutorials that you'll probably find helpful.