python ctypes interface to blcr?

• Previous message: Locus Jackson: "Re: Why do I get the error "cri_syscall(CR_OP_RSTRT_PROCS):Invalid arguments""

Hey, this is fun:
from ctypes import *

class cr_checkpoint_args_t (Structure):
    _fields_ = [("cr_version", c_int),
                ("cr_scope", c_int),
                ("cr_target", c_int),
                ("cr_fd", c_int),
                ("cr_signal", c_int),
                ("cr_timeout", c_int),
                ("cr_flags", c_int)]
    
libcr = CDLL ('/usr/lib64/libcr.so.0')

cr_args = cr_checkpoint_args_t()
cr_args.cr_version = 1
CR_SCOPE_PROC = 1

libcr.cri_initialize_checkpoint_args_t (byref(cr_args))
cr_args.cr_scope = CR_SCOPE_PROC
cr_args.cr_target = 0
cr_args.cr_signal = 0
cr_args.cr_timeout = 0
cr_args.cr_flags = 0

_id = libcr.cr_init()

assert (_id >= 0)


def request_checkpoint (cr_args, cr_handle):
     assert (isinstance (cr_args, cr_checkpoint_args_t))
     assert (isinstance (cr_handle, c_ulong))  # c long
     err = libcr.cr_request_checkpoint (byref(cr_args), byref (cr_handle))
     return err, cr_handle
 
cr_handle = c_ulong()
cp_file = open ("checkpoint", 'w')
cr_args.cr_fd = cp_file.fileno()

err,handle = request_checkpoint (cr_args, cr_handle)

All we need to add is to wait till file write is finished and close the file 
(I think)

• Previous message: Locus Jackson: "Re: Why do I get the error "cri_syscall(CR_OP_RSTRT_PROCS):Invalid arguments""