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.he 'LD (I)'3/15/72'LD (I)'
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NAME		ld  --  link editor
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SYNOPSIS	ld\b\b__ [ -sulxr\b\b\b\b\b\b______ ] name\d1\u ...
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DESCRIPTION	ld\b\b__  combines several
object programs into one; resolves external
references; and searches libraries.
In the simplest case the names of several object
programs are given, and ld\b\b__ combines them, producing
an object module which can be either executed or
become the input for a further ld\b\b__ run.
In the latter case, the "-r" option must be given
to preserve the relocation bits.
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The argument routines are concatenated in the order
specified.  The entry point of the output is the
beginning of the first routine.
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If any argument is a library, it is searched exactly once.
Only those routines defining an unresolved external
reference are loaded.
If a routine from a library
references another routine in the library,
the referenced routine must appear after the
referencing routine in the library.
Thus the order of programs within libraries
is important.
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ld\b\b__ understands several flag arguments which are written
preceded by a "-":
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-s "squash" the output, that is, remove the symbol table
and relocation bits to save space (but impair the
usefulness of the debugger).
This information can also be removed by strip\b\b\b\b\b_____.
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-u take the following argument as a symbol and enter
it as undefined in the symbol table.  This is useful
for loading wholly from a library, since initially the symbol
table is empty and an unresolved reference is needed
to force the loading of the first routine.
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-l This option is an abbreviation for a library name.
"-l" alone stands for "/usr/lib/liba.a", which
is the standard system library for assembly language
programs.
"-lx" stands for "/usr/lib/libx.a" where x is any character.
There are libraries for Fortran (x="f"), C (x="c"), Explor (x="e") and B (x="b").

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-x Do not preserve local
(non-.globl) symbols in the output symbol table; only enter
external symbols.
This option saves some space in the output file.

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-r generate relocation bits in the output file
so that it can be the subject of another ld\b\b__ run.
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The output of ld\b\b__ is left on a.out\b\b\b\b\b_____.  This file is executable
only if no errors occurred during the load.
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FILES		/usr/lib/lib?.a	libraries
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a.out	output file
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SEE ALSO	as(I), ar(I)
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DIAGNOSTICS	"file
not found"-- bad argument
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"bad format"-- bad argument
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"relocation error"-- bad argument (relocation
bits corrupted)
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"multiply defined"-- same symbol defined twice in same load
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"un"-- stands for "undefined symbol"

"symbol not found"--  loader bug

"can't move output file"-- can't move temporary to a.out file

"no relocation bits"-- an input file lacks relocation information

"too many symbols"-- too many references to external
symbols in a given routine

"premature EOF"

"can't create l.out"-- cannot make temporary file

"multiple entry point"-- more than one entry point
specified (not possible yet).
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BUGS		--