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how to get stderr

 
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# 1  
Old 06-15-2011
how to get stderr
Hello

I try to store stderr into a variable, then if this var is not empty i send an email and stop my script.

I think my problem is due of "<$dump" into my command line.

Code:
my bad command line (see samples below on this post)
if ! $returnedStr ; 
 then
     echo ERROR READING DUMP:  $returnedStr
  exit 1
 else
  echo cool ($returnedStr)
 fi

allways returns "cool" even if "my bad command line" throw an error.

Here all syntaxes i tested for "my bad command line":
Code:
exec 2>&1
returnedStr= `mysql -u theuser --password=thepassword < dump.sql`

Code:
returnedStr= `mysql -u theuser --password=thepassword < dump.sql 2>$1`

Code:
mysql -u theuser --password=thepassword < dump.sql 2>>$returnedStr

May someone give me the tips please?
# 2  
Old 06-15-2011
Well, do you have /dev/stderr on your UNIX?

If there is no stdout, it is simple:
Code:
zvar=$( your_command_and_args 2>&1 )

This User Gave Thanks to DGPickett For This Post:
giova
# 3  
Old 06-15-2011
Thank you for answering DGPicket

But unfortunatly your syntaxe didn't works as well :
Code:
returnedStr=$( mysql -u theuser --password=thepassword < dump.sql 2>&1 )

=> ERROR: command not found
also tested :
Code:
returnedStr=$ ( mysql -u theuser --password=thepassword < dump.sql 2>&1 )

=> syntax error near unexpected token `('

And yes i see a stderr@ into /dev/ (also stdin@ and stdout@)
uname says : Linux 2.6.18-238.12.1.el5 x86_64 x86_64 x86_64 GNU/Linux

this is a ssh terminal acces that my web host allowed to me. So for security reason, some files are not into the usual places, but into my local folders.

PS : i'm a really dummy with unix Smilie just trying step by step to make my sh script with caution.

Any other idea? Thanks.
# 4  
Old 06-15-2011
Quote:
Originally Posted by giova
Thank you for answering DGPicket

But unfortunatly your syntaxe didn't works as well :
Code:
returnedStr=$( mysql -u theuser --password=thepassword < dump.sql 2>&1 )

=> ERROR: command not found
also tested :
Code:
returnedStr=$ ( mysql -u theuser --password=thepassword < dump.sql 2>&1 )

=> syntax error near unexpected token `('
Your shell doesn't have $(this syntax). Try "`backticks`"
# 5  
Old 06-15-2011
Is it sort of "Amish" to use the bourne shell, still? Smilie
This User Gave Thanks to DGPickett For This Post:
giova
# 6  
Old 06-15-2011
Depends which...
# 7  
Old 06-15-2011
SmilieThank you So much Corona !
Now it works, i'm totally confused with that QuoteDoubleQuoteBackQuoteUnderQuote syntax, but this now just works like a charms Smilie

I really have to learn how to manage this !

Just to confirm, here the final syntax :
Code:
returnedStr= "`mysql -u theuser --password=thepassword < dump.sql 2>&1`"
if [[ -n "$returnedStr" ]] ; then
  echo ERROR READING DUMP:  $returnedStr
  exit 1
 else
  echo cool ($returnedStr)
 fi

CGPicket > well UNIX shell sounds Armish stylelife when you discover it SmilieSmilie

Thanks again people.
 
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