Getnextvariablename() - Intel Extensible Firmware Interface Specification

Extensible Firmware Interface Specification
3.5.2

GetNextVariableName()

Summary
Enumerates the current variable names.
Prototype
EFI_STATUS
GetNextVariableName (
IN OUT UINTN
IN OUT CHAR16
IN OUT EFI_GUID
);
Parameters
VariableNameSize
VariableName
VendorGuid
Description
GetNextVariableName()
of all variables currently available in the system. On each call to
VendorGuid
GetNextVariableName()
interface returns the next variable name data. When the entire variable list has been returned, the
error
EFI_NOT_FOUND
Note that if
EFI_BUFFER_TOO_SMALL
for the next variable. When such an error occurs, the
the size of buffer needed. In all cases when calling
VariableNameSize
VariableName.
To start the search, a Null-terminated string is passed in VariableName; that is,
is a pointer to a Null Unicode character. This is always done on the initial call to
VariableName
GetNextVariableName(). When
is ignored.
VendorGuid
variable names with a specific GUID. Instead, the entire list of variables must be retrieved, and the
caller may act as a filter if it chooses. Calls to
GetNextVariableName()
80
*VariableNameSize,
*VariableName,
*VendorGuid
The size of the
VariableName
On input, supplies the last
by GetNextVariableName(). On output, returns the Null-
terminated Unicode string of the current variable.
On input, supplies the last
GetNextVariableName(). On output, returns the
of the current variable. Type
VendorGuid
defined in Section 3.3.1.
is called multiple times to retrieve the
the previous results are passed into the interface, and on output the
is returned.
is returned, the
must not exceed the actual buffer size that was allocated for
VariableName
GetNextVariableName()
SetVariable()
may produce unpredictable results.
12/12/00
buffer.
VariableName
that was returned by
VendorGuid
VariableName
buffer was too small
VariableName
VariableNameSize
GetNextVariableName()
is a pointer to a Null Unicode character,
cannot be used as a filter to return
between calls to
that was returned
is
EFI_GUID
and
is updated to reflect
the
Version 1.02