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if [ $? -eq 0 ] .. can someone explain this? if [ $? -eq 0 ] .. can someone explain this?
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Old 10-03-2006
ranjita.c ranjita.c is offline
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Question if [ $? -eq 0 ] .. can someone explain this?
I thought it means if the return code of the previous command not equal to 0...
Is this correct?
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Old 10-03-2006
anbu23 anbu23 is offline Forum Advisor  
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you are correct
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Old 10-03-2006
dsravan dsravan is offline
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No it's not "not equal" but "equal"
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Old 10-03-2006
zeekblack zeekblack is offline
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Quote:
Originally Posted by dsravan
No it's not "not equal" but "equal"

`-eg` = equal
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Old 10-03-2006
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vgersh99 vgersh99 is offline Forum Staff  
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Quote:
Originally Posted by ranjita.c
I thought it means if the return code of the previous command not equal to 0...
Is this correct?
I'd interprete this as 'not equal to 0' which is to say '-ne 0'.
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Old 10-03-2006
BOFH BOFH is offline Forum Advisor  
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The numeric comparisons for korn shell are

numA -eq numB - True if numA and numB are equal
numA -ne numB - True if numA and numB are not equal
numA -lt numB - True if numA is less than numB
numA -gt numB - True if numA is greater than numB
numA -le numB - True if numA is less than or equal to numB
numA -ge numB - True if numA is greater than or equal to numB

the string comparisons for korn shell are

strA = strB - True if strA matches strB
strA != strB - True if strA does not match strB
strA < strB - True if strA comes before strB in a dictionary order
strA > strB - True if strA comes after strB in a dictionary order

So your example says to run the commands between then and fi or else if the return code of the previous command is equal to zero (0).

Carl
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