unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (SunOS-4.1.3)
Page:
Section:
Apropos / Subsearch:
optional field

KVM_OPEN(3K)                                                      KVM_OPEN(3K)



NAME
       kvm_open, kvm_close - specify a kernel to examine

SYNOPSIS
       #include <&lt;kvm.h>&gt;
       #include <&lt;fcntl.h>&gt;

       kvm_t *kvm_open(namelist, corefile, swapfile, flag, errstr)
       char *namelist, *corefile, *swapfile;
       int flag;
       char *errstr;

       int kvm_close(kd)
       kvm_t *kd;

DESCRIPTION
       kvm_open()  initializes  a set of file descriptors to be used in subse-
       quent calls to kernel VM routines.  It returns a pointer  to  a  kernel
       identifier that must be used as the kd argument in subsequent kernel VM
       function calls.

       The namelist argument specifies an  unstripped  executable  file  whose
       symbol  table  will  be used to locate various offsets in corefile.  If
       namelist is NULL, the symbol table of the currently running  kernel  is
       used to determine offsets in the core image.  In this case, it is up to
       the implementation to select an appropriate  way  to  resolve  symbolic
       references (for instance, using /vmunix as a default namelist file).

       corefile  specifies  a  file that contains an image of physical memory,
       for instance, a kernel crash dump file (see savecore(8)) or the special
       device  /dev/mem.  If corefile is NULL, the currently running kernel is
       accessed (using /dev/mem and /dev/kmem).

       swapfile specifies a file that represents the  swap  device.   If  both
       corefile and swapfile are NULL, the swap device of the ``currently run-
       ning kernel'' is accessed.  Otherwise, if swapfile is NULL,  kvm_open()
       may  succeed but subsequent kvm_getu(3K) function calls may fail if the
       desired information is swapped out.

       flag is used to specify read or write access for corefile and may  have
       one of the following values:

              O_RDONLY            open for reading

              O_RDWR              open for reading and writing

       errstr is used to control error reporting.  If it is a NULL pointer, no
       error messages will be printed.  If it is non-NULL, it is assumed to be
       the address of a string that will be used to prefix error messages gen-
       erated by kvm_open.  Errors are printed to stderr.  A useful  value  to
       supply  for  errstr  would be argv[0].  This has the effect of printing
       the process name in front of any error messages.

       kvm_close() closes all file descriptors that were associated  with  kd.
       These  files  are  also closed on exit(2v) and execve(2V).  kvm_close()
       also resets the  proc  pointer  associated  with  kvm_nextproc(3K)  and
       flushes any cached kernel data.

RETURN VALUES
       kmv_open()  returns  a  non-NULL value suitable for use with subsequent
       kernel VM function calls.  On failure, it returns NULL and no files are
       opened.

       kvm_close() returns:

       0      on success.

       -1     on failure.

FILES
       /vmunix
       /dev/kmem
       /dev/mem
       /dev/drum

SEE ALSO
       execve(2V),  exit(2v),  kvm_getu(3K),  kvm_nextproc(3K), kvm_nlist(3K),
       kvm_read(3K), savecore(8)



                                21 January 1990                   KVM_OPEN(3K)