how to make "if" and comparison statement in uboot?

u-boot
Egy Mohammad Erdin picture Egy Mohammad Erdin · Apr 13, 2011 · Viewed 21.1k times · Source

i'm newbie in uboot and tftp programing

based on this url, there is how to make if statement like this if imi $addr; then echo Image OK; else echo Image corrupted!!; fi

and this is my "if" : 

=> setenv a true
=> printenv a
a=true
=> setenv b true
=> printenv b
b=true
=> if a b; then echo 'same';fi
Unknown command 'a' - try 'help'
=> if $a $b; then echo 'same';fi
Unknown command 'true' - try 'help'
=> if ${a} ${b}; then echo 'same';fi
Unknown command 'true' - try 'help'
=>

Answer

vhallac picture vhallac · Apr 13, 2011

I am not sure if it is in all u-boot versions or not, but there should be a test command for comparison. Can you try:

if test "${a}" = "${b}"; then echo "same"; fi

Unfortunately I don't have access to u-boot, so this is all from memory.

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