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problem with variable expansion in shell script

  #1  
Oct 27th, 2007
Dear all,
I have written a small script which will send me mail on status of server.
I have tested it working fine. I am facing only with message subject

The last part of my script is as below,

cat dailystatus.txt| mail -s "Daily Server Status Report-$yr-$mm-$dd" root@ecms.co.in

The script run perfectly . The variable yr, mm. dd are defined and that is not a problem I have tested it too. But when I receive the mail , I got the subject heading as "Daily Server Status Report-$yr-$mm-$dd" . The variable are not getting replaced by the values,
So I feel that it may not be allowed to put variables with mail command.

Is there is any way so that subject can be read from file. Or any other idea on this.
Thanks
Vinod
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Re: problem with variable expansion in shell script

  #2  
Oct 27th, 2007
cat dailystatus.txt| mail -s "Daily Server Status Report-${yr}-${mm}-${dd}" root@ecms.co.in
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Re: problem with variable expansion in shell script

  #3  
Oct 28th, 2007
it should not matter if you put $yr or ${yr}. Show your entire code that defined the variables..
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Re: problem with variable expansion in shell script

  #4  
Oct 28th, 2007
Originally Posted by ghostdog74 View Post
it should not matter if you put $yr or ${yr}.


Maybe not, but it is still a good practice to get into, especially when using variables mixed in with other characters where the variable does not have whitespace on both sides. But, considering that he is actually getting "-$yr-" (which is the first variable) tells me that the script is not recognizing those "strings" as variables, at all, which the braces can help with.

Edit: If it were that the variables were defined wrong, he would probably wind up with "Report---".
Last edited by masijade : Oct 28th, 2007 at 8:38 am.
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Re: problem with variable expansion in shell script

  #5  
Oct 29th, 2007
Thanks all,
It works with ${yr} i.e. putting variables in curly braces.
vinod
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