You could play dirty and supply the input to your pre_backup script from its STDIN directly in the sudo command line: 
sudo sh /usr/local/scripts/pre_backup.sh <`echo "X"`

[download]
Those are backticks, BTW.

OK, this is not exactly what you asked, but in the age old spirit of TIMTOWTDI and getting around annoying limitations that is integral to Perl, it gets the job done (I hope).

Note that, if your script expects input more than once, you'll have to modify the echo to take this into account.

Caveat: I'm not sure how expect spawns its command lines or how sudo spawns its commands, but if a shell is involved anywhere in there, you'll have to get creative with those backticks and quotes to avoid said shell stomping all over it.

CU
Robartes-

Update: Added caveat.

In reply to Re: Expect.pm and sudo. by robartes
in thread Expect.pm and sudo. by sschneid

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