freebsd-skq/contrib/elftoolchain/libdwarf/dwarf_expr_current_offset.3

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.\" Copyright (c) 2011 Kai Wang
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.\" $Id: dwarf_expr_current_offset.3 2073 2011-10-27 03:30:47Z jkoshy $
.\"
.Dd September 13, 2011
.Os
.Dt DWARF_EXPR_CURRENT_OFFSET 3
.Sh NAME
.Nm dwarf_expr_current_offset
.Nd retrieve the number of bytes in a location expression stream
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft "Dwarf_Unsigned"
.Fo dwarf_expr_current_offset
.Fa "Dwarf_P_Expr expr"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_expr_current_offset
returns the size in bytes of the stream representation of a location
expression.
.Pp
Argument
.Ar expr
should reference a location expression descriptor allocated using
.Xr dwarf_new_expr 3 .
.Pp
If argument
.Ar err
is not NULL, it will be used to store error information in case
of an error.
.Sh RETURN VALUES
On success, function
.Fn dwarf_expr_current_offset
returns the size in bytes of the location descriptor's stream
representation.
In case of an error, function
.Fn dwarf_expr_current_offset
returns
.Dv DW_DLV_NOCOUNT
and sets the argument
.Ar err .
.Sh ERRORS
Function
.Fn dwarf_expr_current_offset
can fail with:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
Argument
.Ar expr
was NULL.
.El
.Sh SEE ALSO
.Xr dwarf 3 ,
.Xr dwarf_add_expr_addr 3 ,
.Xr dwarf_add_expr_addr_b 3 ,
.Xr dwarf_add_expr_gen 3 ,
.Xr dwarf_expr_into_block 3 ,
.Xr dwarf_new_expr 3