shell - Bash -value too great for base (error token is "09") for date string yyyymmdd -

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• shell script error: value great base (error token “08”) [duplicate] 1 answer

i trying generate startdate in format yyyymmdd such date 1st day of third last month. example, current month july (07), need start date 1st day of april (04) - 20150401.

in order achieve in bash, used following command:

startdate=$(date -d "-3 month -$(($(date +%d)-1)) days" +"%y%m%d") 

however, giving me following error:

line 93: 09: value great base (error token "09") 

i not want change format of startdate variable. single digit months (1-9), format should have leading 0 infront of month number in yyyymmdd format.

is there missing?

thanks in advance!

bash seeing 09 , trying treat octal number fails.

you can prefix date value 10# force base. see second-to-last paragraph of shell arithmetic.

startdate=$(date -d "-3 month -$((10#$(date +%d)-1)) days" +"%y%m%d")