.TH ARCH 3 "January 11, 2001" "Apple Computer, Inc."
.SH NAME
NXGetAllArchInfos, NXGetLocalArchInfo, NXGetArchInfoFromName,
NXGetArchInfoFromCpuType, NXFindBestFatArch, NXCombineCpuSubtypes
\- get architecture information
.SH SYNOPSIS
.nf
.PP
.ft B
#include <mach-o/arch.h>
.sp .5
.B extern const NXArchInfo *NXGetAllArchInfos(void);
.sp .5
.B extern const NXArchInfo *NXGetLocalArchInfo(void);
.sp .5
.B extern const NXArchInfo *NXGetArchInfoFromName(const char *\fIname\fB);
.sp .5
.B extern const NXArchInfo *NXGetArchInfoFromCpuType(cpu_type_t \fIcputype\fB,
\fBcpu_subtype_t \fIcpusubtype\fB);
.sp .5
.B extern struct fat_arch *NXFindBestFatArch(cpu_type_t \fIcputype\fB,
\fBcpu_subtype_t \fIcpusubtype\fB,
\fBstruct fat_arch *\fIfat_archs\fB,
\fBunsigned long \fInfat_archs\fB);
.sp .5
.B extern cpu_subtype_t NXCombineCpuSubtypes(cpu_type_t \fIcputype\fB,
\fBcpu_subtype_t \fIcpusubtype1\fB,
\fBcpu_subtype_t \fIcpusubtype2\fB);
.SH DESCRIPTION
These functions are intended for use in programs that have to deal with fat
files or programs that can target multiple architectures. Typically, a program
will use a command-line argument that starts with
.BI \-arch " name"\fR,
where this specifies an architecture. These functions and data structures
provide some help for processing architecture flags and then processing
the contents of a fat file.
.PP
The structure NXArchInfo
is defined in
.I <mach-o/arch.h>
as follows:
.nf
typedef struct {
const char *name;
cpu_type_t cputype;
cpu_subtype_t cpusubtype;
enum NXByteOrder byteorder;
const char *description;
} NXArchInfo;
.fi
It is used to hold the name of the architecture and the corresponding CPU type
and CPU subtype, together with the architecture's byte order and a brief description string.
.PP
The currently known architectures are:
.sp
.if t .in +0.1i
.if n .ll \n(LLu+1i
.ta +\w'hppa7100LC 'u +\w'CPU_TYPE_POWERPC 'u +\w'CPU_SUBTYPE_MC68030_ONLY 'u +\w'Intel Pentium II Model 5 'u
.br
\fBName CPU Type CPU Subtype Description\fR
.br
ppc CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_ALL PowerPC
.br
i386 CPU_TYPE_I386 CPU_SUBTYPE_I386_ALL Intel 80x86
.br
m68k CPU_TYPE_MC680x0 CPU_SUBTYPE_MC680x0_ALL Motorola 68K
.br
hppa CPU_TYPE_HPPA CPU_SUBTYPE_HPPA_ALL HP-PA
.br
i860 CPU_TYPE_I860 CPU_SUBTYPE_I860_ALL Intel 860
.br
m88k CPU_TYPE_MC88000 CPU_SUBTYPE_MC88000_ALL Motorola 88K
.br
sparc CPU_TYPE_SPARC CPU_SUBTYPE_SPARC_ALL SPARC
.br
ppc601 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_601 PowerPC 601
.br
ppc603 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_603 PowerPC 603
.br
ppc604 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_604 PowerPC 604
.br
ppc604e CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_604e PowerPC 604e
.br
ppc750 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_750 PowerPC 750
.br
ppc7400 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_7400 PowerPC 7400
.br
ppc7450 CPU_TYPE_POWERPC CPU_SUBTYPE_POWERPC_7450 PowerPC 7450
.br
i486 CPU_TYPE_I386 CPU_SUBTYPE_486 Intel 486
.br
i486SX CPU_TYPE_I386 CPU_SUBTYPE_486SX Intel 486SX
.br
pentium CPU_TYPE_I386 CPU_SUBTYPE_PENT Intel Pentium
.br
i586 CPU_TYPE_I386 CPU_SUBTYPE_586 Intel 586
.br
pentpro CPU_TYPE_I386 CPU_SUBTYPE_PENTPRO Intel Pentium Pro
.br
pentIIm3 CPU_TYPE_I386 CPU_SUBTYPE_PENTII_M3 Intel Pentium II Model 3
.br
pentIIm5 CPU_TYPE_I386 CPU_SUBTYPE_PENTII_M5 Intel Pentium II Model 5
.br
m68030 CPU_TYPE_MC680x0 CPU_SUBTYPE_MC68030_ONLY Motorola 68030
.br
m68040 CPU_TYPE_MC680x0 CPU_SUBTYPE_MC68040 Motorola 68040
.br
hppa7100LC CPU_TYPE_HPPA CPU_SUBTYPE_HPPA_7100LC HP-PA 7100LC
.if t .in -0.1i
.if n .ll \n(LLu
.PP
The first set of entries
are used for the architecture family. The second set of entries are used for a specific
architecture, when more than one specific architecture is supported in a
family of architectures.
.PP
.IR NXGetAllArchInfos ()
returns a pointer to an array of all known
NXArchInfo structures. The last NXArchInfo is marked by a
.SM NULL
name.
.PP
.IR NXGetLocalArchInfo ()
returns the NXArchInfo for the local host, or
.SM NULL
if none is known.
.PP
.IR NXGetArchInfoFromName ()
and
.IR NXGetArchInfoFromCpuType ()
return the NXArchInfo
from the architecture's name or CPU type/CPU subtype
combination. A CPU subtype of
.SM CPU_SUBTYPE_MULTIPLE
can be used
to request the most general NXArchInfo
known for the given CPU type.
.SM NULL
is returned if no matching NXArchInfo
can be found.
.PP
.IR NXFindBestFatArch ()
is passed a CPU type and CPU subtype and a set of
fat_arch structs. It selects the best one that matches (if any), and returns
a pointer to that fat_arch struct (or \s-1NULL\s+1).
The fat_arch structs must be
in the host byte order and correct such that
.I fat_archs
really points to
enough memory for
.I nfat_arch
structs. It is possible that this routine could
fail if new CPU types or CPU subtypes are added and an old version of this
routine is used. But if there is an exact match between the CPU type and
CPU subtype and one of the fat_arch structs, this routine will always succeed.
.PP
.IR NXCombineCpuSubtypes ()
returns the resulting CPU subtype when combining two
different CPU subtypes for the specified CPU type. If the two CPU subtypes
can't be combined (the specific subtypes are mutually exclusive), \-1 is
returned, indicating it is an error to combine them. This can also fail and
return \-1 if new CPU types or CPU subtypes are added and an old version of
this routine is used. But if the CPU subtypes are the same, they can always
be combined and this routine will return the CPU subtype passed in.
.\" .SH "SEE ALSO"
.\" .IR arch (1)