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Iyyappan

11-24-2012 03:35 PM

[: : integer expression expected if else condition

Hi All,
I am in need of sending a mail on every fourth sunday of month. I have written the script like this

Code:

MAILSUBJECT="test mail"

MAILTO="test@test.org"

MAILBODY="Test Mail for you"

DATE=$(/bin/date -I)

DAY=$(date "+%d")

FOURTH_SUNDAY=$(cal | tail -n 2 | awk '{print $1}')



if [ "$DAY" -eq "$FOURTH_SUNDAY" ]; then



echo "success"

echo "$MAILBODY" | $MUTT -e 'set content_type="text/html"' $MAILTO -s "$MAILSUBJECT"

else 

echo "failure"

exit 0

fi

When I execute the script I receive
integer expression expected error:

If I manually specify the date instead of FOURTH_SUNDAY, script gets executed. Kindly let me know, if there is any work around

acid_kewpie

11-24-2012 04:03 PM

there is no "workaround", there's using commands properly ;-)

the string you're getting out of cal has two lines in it, a blank one at the end, so it's not an integer you're getting out of it. I expect there's a better way to get the last month of a month, but my brains switched off for now. If you "head -n1" the output, that'll ditch the blank line.

colucix

11-24-2012 04:32 PM

This condition identifies the fourth Sunday of the month:

Code:

[[ $(date +%w) -eq 0 && $(date +%d) -ge 22 && $(date +%d) -le 28 ]]

:twocents:

Iyyappan

11-24-2012 05:48 PM

I tried with head command, but received same error

Code:

MAILSUBJECT="test mail"

MAILTO="test@test.org"

MAILBODY="Test Mail for you"

DATE=$(/bin/date -I)

DAY=$(date "+%d")

FOURTH_SUNDAY=$(cal | head -n 7 | tail -n 1 | awk '{print $1}')



if [ "$DAY" -eq "$FOURTH_SUNDAY" ]; then



echo "success"

echo "$MAILBODY" | $MUTT -e 'set content_type="text/html"' $MAILTO -s "$MAILSUBJECT"

else

echo "failure"

exit 0

fi

colucix

11-25-2012 02:09 AM

Your last example should work, since it retrieves a single value with no extra lines from the calendar. Anyway, using cal in this way is not a robust method to retrieve the 4th Sunday of the month: for example, compare July and November of this year:

Code:

      July 2012            November 2012

Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa

 1  2  3  4  5  6  7                1  2  3

 8  9 10 11 12 13 14    4  5  6  7  8  9 10

15 16 17 18 19 20 21  11 12 13 14 15 16 17

22 23 24 25 26 27 28  18 19 20 21 22 23 24

29 30 31              25 26 27 28 29 30

In the first case with your command you get the 5th Sunday of the month, in the second case the 4th.

Therefore, why not using a more robust method as suggested previously? For example, consider that the 4th Sunday of the month is always included in the week between the 22nd and the 28th of the month, so that:

Code:

if [[ $(date +%w) -eq 0 && $(date +%d) -ge 22 && $(date +%d) -le 28 ]]

then

  echo do something

fi

should do the trick.

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