1 .\" Copyright (c) 1999 Global Technology Associates, Inc.
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42 utility compresses a kernel or some other bootable binary. Operation
43 is in two phases as follows:
46 A load image of the executable file is built which omits all but
51 segments. This image is compressed using
53 and output as data in relocatable object format.
55 The object file is linked with a special self-hosting loader, producing
56 an executable suitable for booting with either the second- or
57 third-level bootstraps.
60 Supported input formats are ELF and a.out ZMAGIC; the output format
61 is always ELF. Only 32-bit objects are supported.
67 suffix, input is assumed to be for the link phase, and the first phase
75 Display object file information.
83 The default is to use the input name with the suffix
90 Global variables equivalent to the following are defined in the output:
93 char ident[4]; /* identification: "KGZ" */
94 uint32_t dload; /* decoded image load address */
95 uint32_t dsize; /* decoded image size */
96 uint32_t isize; /* image size in memory */
97 uint32_t entry; /* entry point */
98 uint32_t nsize; /* encoded image size */
101 uint8_t kgz_ndata[]; /* encoded data */
104 The encoded data is simply
106 output: a header (with no optional fields); compressed data; and 32-bit
109 .Bl -tag -width /usr/lib/kgzldr.o -compact
110 .It Pa /usr/lib/kgzldr.o
121 Exit status is 0 on success and >0 on error.
123 .An Robert Nordier Aq rnordier@FreeBSD.org .
125 As symbols are lost, the usefulness of this utility for compressing
126 kernels is limited to situations where
128 cannot be used; otherwise the preferred method of compressing a kernel