printenv command

Synopsis

printenv [-a] [name ...]
printenv -e [-guid guid][-n] [name]

Description

The printenv command is used to print environment or UEFI variables.

-a

Print environment variables starting with a period (‘.’).

-e

Print UEFI variables. Without -e environment variables are printed.

-guid guid

Specify vendor GUID guid. If none is specified, all UEFI variables with the specified name are printed irrespective of their vendor GUID.

-n

don’t show hexadecimal dump of value

name

Variable name. If no name is provided, all variables are printed. Multiple environment variable names may be specified.

Examples

The following examples demonstrates the effect of the -a flag when displaying environment variables:

=> setenv .foo bar
=> printenv
arch=sandbox
baudrate=115200
board=sandbox
...
stdout=serial,vidconsole

Environment size: 644/8188 bytes
=> printenv -a
.foo=bar
arch=sandbox
baudrate=115200
board=sandbox
...
stdout=serial,vidconsole

Environment size: 653/8188 bytes
=>

The next example shows the effect of the -n flag when displaying an UEFI variable and how to specify a vendor GUID:

=> printenv -e -guid 8be4df61-93ca-11d2-aa0d-00e098032b8c PlatformLangCodes
PlatformLangCodes:
    8be4df61-93ca-11d2-aa0d-00e098032b8c (EFI_GLOBAL_VARIABLE_GUID)
    BS|RT|RO, DataSize = 0x6
    00000000: 65 6e 2d 55 53 00                                en-US.
=> printenv -e -n PlatformLangCodes
PlatformLangCodes:
    8be4df61-93ca-11d2-aa0d-00e098032b8c (EFI_GLOBAL_VARIABLE_GUID)
    BS|RT|RO, DataSize = 0x6
=>

Configuration

UEFI variables are only supported if CONFIG_CMD_NVEDIT_EFI=y. The value of UEFI variables can only be displayed if CONFIG_HEXDUMP=y.

Return value

The return value $? is 1 (false) if a specified variable is not found. Otherwise $? is set to 0 (true).