DATES with awk in UNIX [duplicate] - bash

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take date from file in unix
(1 answer)
Closed 6 years ago.
I want to take two dates as argument from the user ( ) with
$./tool.sh --born-since <dateA> --born-until <dateB>
and from a file print the lines that are between those two dates.For example:
933|Mahinda|Perera|male|1989-12-03|2010-03-17T13:32:10.447+0000|192.248.2.123|Firefox
1129|Carmen|Lepland|female|1984-02-18|2010-02-28T04:39:58.781+0000|81.25.252.111|Internet Explorer
4194|Hồ Chí|Do|male|1988-10-14|2010-03-17T22:46:17.657+0000|103.10.89.118|Internet Explorer
So , i use awk command like this :
awk -F'|' '{print $4} [ file ... ]
to take the dates .. how can i use awk to make the dates from the txt to seconds form ?

Answer 1

if the date variables are in the same format, you can convert everything to numbers and use comparison.
awk -F'|' -v from=$dateA -v to=$dateB '{gsub("-","",$5);
gsub("-","",from); gsub("-","",to)}
from <= $5 && $5 <= to' file
Note, it's the fifth field in your file.

Answer 2

You can either call the /bin/date +"%s" --date="DATESTRING" through system() if the DATESTRING matches a format "/bin/date" understands, or you use the internal mktime() function. But then you need to split your date according to awk(1):
mktime(datespec)
Turn datespec into a time stamp of the same form as returned by systime(), and return the result. The datespec is a string of
the form YYYY MM DD HH MM SS[ DST]. The contents of the string are six or seven numbers representing respectively the full year
including century, the month from 1 to 12, the day of the month from 1 to 31, the hour of the day from 0 to 23, the minute from 0
to 59, the second from 0 to 60, and an optional daylight saving flag. The values of these numbers need not be within the ranges
specified; for example, an hour of -1 means 1 hour before midnight. The origin-zero Gregorian calendar is assumed, with year 0
preceding year 1 and year -1 preceding year 0. The time is assumed to be in the local timezone. If the daylight saving flag is
positive, the time is assumed to be daylight saving time; if zero, the time is assumed to be standard time; and if negative (the
default), mktime() attempts to determine whether daylight saving time is in effect for the specified time. If datespec does not
contain enough elements or if the resulting time is out of range, mktime() returns -1.
So you need to prepare your date fields to use the form given in the documentation.
split($5, D, "-");
DS = sprintf("%4d %2d %2d 00 00 00", D[1], D[2], D[3]);
T = mktime(DS);
should do the job.