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88 lines
1.8 KiB
ReStructuredText
88 lines
1.8 KiB
ReStructuredText
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.. SPDX-License-Identifier: GPL-2.0+:
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askenv command
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===============
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Synopsis
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--------
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::
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askenv name [message] [size]
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Description
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-----------
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Display message and get environment variable name of max size characters
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from stdin.
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name
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name of the environment variable
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message
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message is displayed while the command waits for the value to be
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entered from stdin.if no message is specified,a default message
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"Please enter name:" will be displayed.
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size
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maximum number of characters that will be stored in environment
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variable name.this is in decimal number format (unlike in
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other commands where size values are in hexa-decimal). Default
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value of size is 1023 (CONFIG_SYS_CBSIZE - 1).
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Example
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-------
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Value of a environment variable env1 without message and size parameters:
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::
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=> askenv env1;echo $?
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Please enter 'env1': val1
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0
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=> printenv env1
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env1=val1
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Value of a environment variable env2 with message and size parameters:
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::
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=> askenv env2 Please type-in a value for env2: 10;echo $?
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Please type-in a value for env2: 1234567890123
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0
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=> printenv env2
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env2=1234567890
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Value of a environment variable env3 with size parameter only:
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::
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=> askenv env3 10;echo $?
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Please enter 'env3': val3
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0
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=> printenv env3
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env3=val3
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Return Value of askenv command, when used without any other arguments:
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::
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=> askenv;echo $?
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askenv - get environment variables from stdin
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Usage:
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askenv name [message] [size]
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- display 'message' and get environment variable 'name' from stdin (max 'size' chars)
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1
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Configuration
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-------------
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The askenv command is only available if CMD_ASKENV=y
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Return value
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------------
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The return value $? is set to 0 (true).
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If no other arguments are specified (along with askenv), it is set to 1 (false).
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