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).