+@node Selecting The Target System
+@chapter Selecting the target system
+
+You can specify three aspects of the target system to the @sc{gnu}
+binary file utilities, each in several ways:
+
+@itemize @bullet
+@item
+the target
+
+@item
+the architecture
+
+@item
+the linker emulation (which applies to the linker only)
+@end itemize
+
+In the following summaries, the lists of ways to specify values are in
+order of decreasing precedence. The ways listed first override those
+listed later.
+
+The commands to list valid values only list the values for which the
+programs you are running were configured. If they were configured with
+@samp{--with-targets=all}, the commands list most of the available
+values, but a few are left out; not all targets can be configured in at
+once because some of them can only be configured @dfn{native} (on hosts
+with the same type as the target system).
+
+@menu
+* Target Selection::
+* Architecture Selection::
+* Linker Emulation Selection::
+@end menu
+
+@node Target Selection
+@section Target Selection
+
+A @dfn{target} is an object file format. A given target may be
+supported for multiple architectures (@pxref{Architecture Selection}).
+A target selection may also have variations for different operating
+systems or architectures.
+
+The command to list valid target values is @samp{objdump -i}
+(the first column of output contains the relevant information).
+
+Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
+@samp{a.out-sunos-big}.
+
+@subheading @code{objdump} Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{-b} or @samp{--target}
+
+@item
+environment variable @code{GNUTARGET}
+
+@item
+deduced from the input file
+@end enumerate
+
+@subheading @code{objcopy} and @code{strip} Input Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
+
+@item
+environment variable @code{GNUTARGET}
+
+@item
+deduced from the input file
+@end enumerate
+
+@subheading @code{objcopy} and @code{strip} Output Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
+
+@item
+the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
+
+@item
+environment variable @code{GNUTARGET}
+
+@item
+deduced from the input file
+@end enumerate
+
+@subheading @code{nm}, @code{size}, and @code{strings} Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{--target}
+
+@item
+environment variable @code{GNUTARGET}
+
+@item
+deduced from the input file
+@end enumerate
+
+@subheading Linker Input Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{-b} or @samp{--format}
+(@pxref{Options,,Options,ld.info,Using LD})
+
+@item
+script command @code{TARGET}
+(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
+
+@item
+environment variable @code{GNUTARGET}
+(@pxref{Environment,,Environment,ld.info,Using LD})
+
+@item
+the default target of the selected linker emulation
+(@pxref{Linker Emulation Selection})
+@end enumerate
+
+@subheading Linker Output Target
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{-oformat}
+(@pxref{Options,,Options,ld.info,Using LD})
+
+@item
+script command @code{OUTPUT_FORMAT}
+(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
+
+@item
+the linker input target (see ``Linker Input Target'' above)
+@end enumerate
+
+@node Architecture Selection
+@section Architecture selection
+
+An @dfn{architecture} is a type of @sc{cpu} on which an object file is
+to run. Its name may contain a colon, separating the name of the
+processor family from the name of the particular @sc{cpu}.
+
+The command to list valid architecture values is @samp{objdump -i} (the
+second column contains the relevant information).
+
+Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
+
+@subheading @code{objdump} Architecture
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{-m} or @samp{--architecture}
+
+@item
+deduced from the input file
+@end enumerate
+
+@subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
+
+Ways to specify:
+
+@enumerate
+@item
+deduced from the input file
+@end enumerate
+
+@subheading Linker Input Architecture
+
+Ways to specify:
+
+@enumerate
+@item
+deduced from the input file
+@end enumerate
+
+@subheading Linker Output Architecture
+
+Ways to specify:
+
+@enumerate
+@item
+script command @code{OUTPUT_ARCH}
+(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
+
+@item
+the default architecture from the linker output target
+(@pxref{Target Selection})
+@end enumerate
+
+@node Linker Emulation Selection
+@section Linker emulation selection
+
+A linker @dfn{emulation} is a ``personality'' of the linker, which gives
+the linker default values for the other aspects of the target system.
+In particular, it consists of
+
+@itemize @bullet
+@item
+the linker script
+
+@item
+the target
+
+@item
+several ``hook'' functions that are run at certain stages of the linking
+process to do special things that some targets require
+@end itemize
+
+The command to list valid linker emulation values is @samp{ld -V}.
+
+Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
+
+Ways to specify:
+
+@enumerate
+@item
+command line option: @samp{-m}
+(@pxref{Options,,Options,ld.info,Using LD})
+
+@item
+environment variable @code{LDEMULATION}
+
+@item
+compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
+which comes from @code{EMUL} in @file{config/@var{target}.mt}
+@end enumerate
+
+@node Index
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