[U-Boot] strange behaviors with setexpr syntax error and '==' != '-eq"
Hi,
I write a script on u-boot but i found 2 strange behaviors.
The first one is when I try to do a mask from a memory address and store it to an env variable.
=> setexpr toto *{loadaddr} & 0xFF syntax error => setexpr toto *{loadaddr} & 0x3F syntax error => setexpr toto 0x3F & *{loadaddr} syntax error
The second one is the difference between '==' and '-eq'
=> setenv a 1 => setenv b 2 => if test ${a} -eq ${b}; then echo toto; fi; => if test ${a} == ${b}; then echo toto; fi; toto
Which doesn't seem logic.
Could you please explain me these behaviors ?
Thanks, Clement
Dear Clément Péron,
In message CAJiuCcfNUtBYnHbs+9WGg00gLskVOQBi6EHk9aJ1+iL5OnJJsg@mail.gmail.com you wrote:
I write a script on u-boot but i found 2 strange behaviors.
I'm tempted to rephrase: you made some errors :-)
The first one is when I try to do a mask from a memory address and store it to an env variable.
=> setexpr toto *{loadaddr} & 0xFF syntax error => setexpr toto *{loadaddr} & 0x3F syntax error => setexpr toto 0x3F & *{loadaddr} syntax error
This has nothing to dowith the setexpr command - the error message comes from the shell. It will issue the same error for other uses of an (unmasked) ampersand:
-> echo a & echo b syntax error
Note: you must always escape special characters.
Also, you probably want to write ${loadaddr} (mind the dollar character).
So try:
setexpr toto *${loadaddr} '&' 0xFF
The second one is the difference between '==' and '-eq'
=> setenv a 1 => setenv b 2 => if test ${a} -eq ${b}; then echo toto; fi; => if test ${a} == ${b}; then echo toto; fi; toto
Which doesn't seem logic.
Well, did you read the man page for the test command?
== is operating on STRING arguments, while -eq is operating on INTEGER arguments. So depending on the content of your variables the result may be the same or different.
Best regards,
Wolfgang Denk
Dear Wolfgang Denk,
Thanks a lot for your explanations ! Clement
I'm tempted to rephrase: you made some errors :-)
The first one is when I try to do a mask from a memory address and store it to an env variable.
=> setexpr toto *{loadaddr} & 0xFF syntax error => setexpr toto *{loadaddr} & 0x3F syntax error => setexpr toto 0x3F & *{loadaddr} syntax error
This has nothing to dowith the setexpr command - the error message comes from the shell. It will issue the same error for other uses of an (unmasked) ampersand:
-> echo a & echo b syntax error
Note: you must always escape special characters.
Also, you probably want to write ${loadaddr} (mind the dollar character).
So try:
setexpr toto *${loadaddr} '&' 0xFFThe second one is the difference between '==' and '-eq'
=> setenv a 1 => setenv b 2 => if test ${a} -eq ${b}; then echo toto; fi; => if test ${a} == ${b}; then echo toto; fi; toto
Which doesn't seem logic.
Well, did you read the man page for the test command?
== is operating on STRING arguments, while -eq is operating on INTEGER arguments. So depending on the content of your variables the result may be the same or different.
Best regards,
Wolfgang Denk
-- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de COBOL is for morons. -- E.W. Dijkstra
participants (2)
-
Clément Péron -
Wolfgang Denk