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Top Forums Shell Programming and Scripting Do something only that last iteration of loop Post 302770096 by Corona688 on Thursday 14th of February 2013 12:15:16 PM
Old 02-14-2013
If it's something you only do once, it t really belong in a function you call 10,000 times. Do it before the loop.

This is especially true since the value of `date` may change if your script takes a long time to finish! Even if it doesn't, you're running date 10,000 times when all you needed was to run it once. Save it into a variable.

What is this if [ $2 ] ? I suspect that doesn't do what you think it does.

Code:
DATE=`date`

function() {
        echo asdf
}

mkdir mydir_${DATE}

while ...
do
        function ...
done

 

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date(1) 						      General Commands Manual							   date(1)

Name
       date - print date and time

Syntax
       date [-c | -u] [ +format ] [[yy[mm[dd]]]hhmm[.ss][-[-]tttt][z]]

Description
       If no argument is given, or if the argument begins with +, the current date and time are printed.  Otherwise, the current date is set.  The
       first mm is the month number; dd is the day number in the month; hh is the hour number (24 hour clock); the second mm is the minute number;
       .ss  the second; -[-]tttt is the minutes west of Greenwich; a positive number means your time zone is west of Greenwich (for example, North
       and South America) and a negative number means it is east of Greenwich (for example Europe); z is a one letter code indicating the dst cor-
       rection mode (n=none, u=usa, a=australian, w=western europe, m=middle europe, e=eastern europe); yy is the last 2 digits of the year number
       and is optional.  The following example sets the date to Oct 8, 12:45 AM:
       date 10080045
       The current year is the default if no year is mentioned.  The system operates in GMT.  The takes care of the conversion to and  from  local
       standard and daylight time.

       If  the	argument begins with +, the output of is under the control of the user.  The format for the output is similar to that of the first
       argument to All output fields are of fixed size (zero padded if necessary).  Each field descriptor is preceded by % and is replaced in  the
       output by its corresponding value.  A single % is encoded by %%.  All other characters are copied to the output without change.	The string
       is always terminated with a new-line character.

Options
       -c     Perform operations using Coordinated Universal Time (UCT) instead of the default local time. The UCT does not use  leap  seconds	so
	      UCT is the same as GMT.

       -u     Perform operations using Greenwich Mean Time (GMT) instead of the default local time.

       + format
	      The following is a list of field Descriptors that can be used in the format (Note: date exits after processing format information) :

		 %a   Locale's abbreviated weekday name

		 %A   Locale's full weekday name

		 %b   Locale's abbreviated month name

		 %B   Locale's full month name

		 %c   Locale's date and time representation

		 %d   Day of month as a decimal number (01-31)

		 %D   Date (%m/%d/%y)

		 %h   Locale's abbreviated month name

		 %H   Hour as a decimal number (00-23)

		 %I   Hour as a decimal number (01-12)

		 %j   Day of year (001-366)

		 %m   Number of month (01-12)

		 %M   Minute number (00-59)

		 %n   Newline character

		 %p   Locale's equivalent to AM or PM

		 %r   Time in AM/PM notation

		 %S   Second number (00-59)

		 %t   Tab character

		 %T   Time (%H/%M/%S)

		 %U   Week number (00-53), Sunday as first day of week

		 %w   Weekday number (0[Sunday]-6)

		 %W   Week number (00-53), Monday as first day of week

		 %x   Locale's date representation

		 %X   Locale's time representation

		 %y   Year without century (00-99)

		 %Y   Year with century

		 %Z   Timezone name, no characters if no timezone

		 %%   %

Examples
       The following command line
       date +%m/%d/%y
       generates the following output
       04/02/89
       The following command line
       date +"DATE: %m/%d/%y%nTIME: %H:%M:%S"
       generates the following output
       DATE: 04/02/89
       TIME: 14:45:05
       The quotes (") are necessary because the format contains blank characters. Use single quotes (') to prevent interpretation by the shell.

Diagnostics
       Failed to set date: Not owner
	    You are not the super-user and you tryed to change the date.  Do not change the date while the system is running in multiuser mode.

Restrictions
       An attempt to set a date to before 1/1/1970 will result in the date being set to 1/1/1970.

Files
       /dev/kmem

																	   date(1)
All times are GMT -4. The time now is 02:13 PM.
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