NAME
libefivar —
EFI Non Volatile Variable
Support
LIBRARY
library “libefivar”
SYNOPSIS
#include
<efivar.h>
int
efi_append_variable(efi_guid_t
guid, const char
*name, uint8_t
*data, size_t
data_size, uint32_t
attributes);
int
efi_del_variable(efi_guid_t
guid, const char
*name);
int
efi_get_variable(efi_guid_t
guid, const char
*name, uint8_t
**data, size_t
*data_size, uint32_t
*attributes);
int
efi_get_variable_attributes(efi_guid_t
guid, const char
*name, uint32_t
*attributes);
int
efi_get_variable_size(efi_guid_t
guid, const char
*name, size_t
*size);
int
efi_get_next_variable_name(efi_guid_t
**guid, char
**name);
int
efi_guid_to_name(efi_guid_t
*guid, char
**name);
int
efi_guid_to_symbol(efi_guid_t
*guid, char
**symbol);
int
efi_guid_to_str(const
efi_guid_t *guid, char
**sp);
int
efi_name_to_guid(const
char *name, efi_guid_t
*guid);
int
efi_set_variable(efi_guid_t
guid, const char
*name, uint8_t
*data, size_t
data_size, uint32_t
attributes, mode_t
mode);
int
efi_str_to_guid(const
char *s, efi_guid_t
*guid);
int
efi_variables_supported(void);
DESCRIPTION
Thelibefivar library implements access to EFI Variables
via the EFI Runtime Serivces. All char * strings are converted to 16-bit UTF
strings before passing them to EFI.
efi_variables_supported()
returns non-zero if the current machine supports setting of EFI firmware
variables and the kernel support for doing so is present. Otherwise zero is
returned.
efi_del_variable()
deletes the EFI variable selected by guid and
name.
efi_get_variable()
efi_get_variable_attributes()
efi_get_variable_size()
efi_append_variable()
efi_set_variable()
efi_get_next_variable_name()
efi_str_to_guid()
efi_guid_to_str()
efi_name_to_guid()
efi_guid_to_name()
efi_guid_to_symbol()
This function is not actually implemented.
SEE ALSO
AUTHORS
This software was originally written by Warner Losh.
BUGS
No facilities exist to process the strings as native UTF. This is a limitation in the Linux libefivar library interface.