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The .IMPORT
directive allows symbols to be defined in one program but used in
other programs. Syntax | |
.IMPORT symbol
[, type] [, TSPECIFIC] Parameters | |
- symbol
The name of an identifier whose definition is being
imported. - type
A linker symbol type that can take one of the following
values: Title not available (Parameters ) - ABSOLUTE
Designates an absolute symbol. - DATA
Designates a data symbol. - CODE
Designates a code location. The location can not
be a procedure entry. - ENTRY
Designates the entry point of a procedure. - MILLICODE
Locates code for the entry point of a millicode
routine. - MILLI_EXT
Locates code for the entry point of an external
millicode routine. - PLABEL
Locates a pointer to a procedure. - PRI_PROG
Designates the primary program entry point. The
outer block of HP Pascal/HP-UX and the main program in HP FORTRAN
77/HP-UX are type PRI_PROG. - SEC_PROG
Designates a secondary program entry point.
- TSPECIFIC
The TSPECIFIC keyword
indicates that this is a thread local storage symbol.
Discussion | |
The .IMPORT
directive uses a series of keywords to define a symbol to the linker.
These keywords declare the symbol's type. Because the .IMPORT
directive specifies that another object module contains this symbol's
formal definition, the Assembler does not associate an imported
symbol with any particular subspace. When an .IMPORT
directive lacks a type parameter, the
Assembler assigns the type of the current subspace (either $CODE$
or $DATA$) to
the symbol. Example | |
The .IMPORT
directive lets the Assembler access symname
as a recognized symbol, even though it is actually defined elsewhere.
The linker resolves the difference. .IMPORT symname,CODE ;import symname as a CODE symbol.
.CODE ;begin CODE subspace
LDIL L'symname,%r1
BLE,n R'symname(%sr4,%r1) ;call the procedure symname in %sr4 space.
NOP
.END
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