NAME    [Toc]    [Back]

     kvm_dump_mkheader, kvm_dump_wrtheader, kvm_dump_inval - crash-dump support
 functions

LIBRARY    [Toc]    [Back]

     Kernel Data Access Library (libkvm, -lkvm)

SYNOPSIS    [Toc]    [Back]

     #include <kvm.h>

     int
     kvm_dump_mkheader(kvm_t *kd, off_t dump_off);

     int
     kvm_dump_wrtheader(kvm_t *kd, FILE *fp, int dumpsize);

     int
     kvm_dump_inval(kvm_t *kd);

DESCRIPTION    [Toc]    [Back]

     First note that the functions described here were designed to be used by
     savecore(8).

     The function kvm_dump_mkheader() checks if the physical memory file associated
 with kd contains a valid crash-dump header as generated by a dumping
 kernel. When a valid header is found, kvm_dump_mkheader() initializes
     the internal kvm data structures as if a crash-dump generated by the
     savecore(8) program was opened. This has the intentional side effect of
     enabling the address translation machinery.

     A call to kvm_dump_mkheader() will most likely be followed by a call to
     kvm_dump_wrtheader().  This function takes care of generating the generic
     header, the CORE_CPU section and the section header of the CORE_DATA section.
 The data is written to the file pointed at by fp.  The dumpsize
     argument is only used to properly the set the segment size of the
     CORE_DATA section. Note that this function assumes that fp is positioned
     at file location 0. This function will not seek and therefore allows fp
     to be a file pointer obtained by zopen().

     The kvm_dump_inval() function clears the magic number in the physical
     memory file associated with kd.  The address translations must be enabled
     for this to work (thus assuming that kvm_dump_mkheader() was called earlier
 in the sequence).

RETURN VALUES    [Toc]    [Back]

     All functions except kvm_dump_mkheader() return 0 on success, -1 on failure.
 The function kvm_dump_mkheader() returns the size of the headers
     present before the actual dumpdata starts. If no valid headers were found
     but no fatal errors occurred, 0 is returned. On fatal errors the return
     value is -1.

     In the case of failure, kvm_geterr(3) can be used to retrieve the cause
     of the error.

SEE ALSO    [Toc]    [Back]

     kvm(3), kvm_open(3)

HISTORY    [Toc]    [Back]

     These functions first appeared in NetBSD 1.2.

BSD                             March 17, 1996                             BSD