Login or Register to Ask a Question and Join Our Community


UNIX for Dummies Questions & Answers

subtraction from date

 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers subtraction from date
# 1  
Old 06-19-2007
subtraction from date
hi gurus!
i realize that my question shows my stupidness, but i need your help!

i have:
Code:
s_date=`date +%m-%d-%Y_%I%p`

variable and i need the same, but minus one hour..
what i made:
Code:
s_date=time(`date +%m-%d-%Y_%I%p`) - 3600

but i'm getting:
Code:
daily_exports.sh: line 20: syntax error near unexpected token `('
daily_exports.sh: line 20: `new_date=time()-3600'

also i did:
Code:
new_date=time()-3600
s_date=strftime(`date +%m-%d-%Y_%I%p`, new_date);

etc.. nothing works,
please, help!

Thank you beforehand,
Maria.
Last edited by Yogesh Sawant; 05-20-2010 at 10:50 AM.. Reason: added code tags
# 2  
Old 06-19-2007
Maria,
Date calculation can be very involved as you have to consider
end of month, end of year, leap year, etc.
Here is a thread that can help you in this issue:
https://www.unix.com/answers-to-frequ...rithmetic.html
# 3  
Old 06-19-2007
Oh, thank you for your help!
this is great source!

Thanks,
Maria.
# 4  
Old 06-19-2007
still fighting. I'll really appreciate any help.
thank you,
M.
# 5  
Old 06-19-2007
cool, i found!
Code:
date -d "-1 hour"

works pefectly,
thank you!
Last edited by Yogesh Sawant; 05-20-2010 at 10:50 AM.. Reason: added code tags
 
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Date Subtraction

Hello All, I am a newbie to unix shell scripting and need to write a script that displays the difference between two variables that stores date value. For example, F1=`ls -ltr file1* | tail -1 |tr -s ' ' |cut -d' ' -f6,7,8` F2=`ls -ltr file2* | tail -1 |tr -s ' ' |cut -d' ' -f6,7,8` F1... (3 Replies)
Discussion started by: priyaa2010
3 Replies

2. Shell Programming and Scripting

Need Help on date subtraction

I have dates as follows in a file 20121029135649 20121029135721 20121030091540 20121030093420 20121030094340 20121030095427 20121030095856 20121030100104 20121030100251 All these dates are in sorted order. I need to find out the difference between the dates as follows 2nd row... (6 Replies)
Discussion started by: meetsriharsha
6 Replies

3. Shell Programming and Scripting

Subtraction using arrays

Hello all . I have two arrays. ${ARRAY_MOUNT_POINT_CAPACITY} ${ARRAY_MOUNT_POINT_CAPACITY}. Whats the synatx of subtracting their values , placing them in variable V1 and then echoeing it ??? Ive tried expr and let ...gives me ./test_code.sh: difference: bad number (3 Replies)
Discussion started by: Junaid Subhani
3 Replies

4. Shell Programming and Scripting

Subtraction

Hi #!/bin/sh month=`date +%m` year=`date +%Y` echo $month a=02 # Retaining Data for Current and Previous Month lmonth=`expr $month - $a` if test "$lmonth" = "0" then lmonth=12 year=`expr $year - 1` fi echo $year echo $lmonth The output is (3 Replies)
Discussion started by: Abhayman
3 Replies

5. Shell Programming and Scripting

Date Subtraction with time.

HI gurus... I have a PERL file that help me extract the date and time of the file. The format of this is: yyyymmddhhmmss. Example: 20100430070935 (April 30 2010 07:09:35) How can i subtract the acquired time from system's time..?? The answer... (6 Replies)
Discussion started by: bankimmehta
6 Replies

6. Shell Programming and Scripting

use of uninitialized value in subtraction

Hallo all i am trying to execute this script ............... But this is throwing the error...... use of uninitialized value in subtraction in at icd_convert.pl line 156 use of uninitialized value in subtraction in at icd_convert.pl line 157 use of uninitialized value in subtraction in at... (1 Reply)
Discussion started by: suvenduperl
1 Replies

7. Shell Programming and Scripting

Date subtraction

hi, i set up a script on my server to do a particular task once files from an external system are ftpd in the format compaq_20100110 (YYDDMM). Interestingly, the source of ftp is sending the files in the format e.g 20100109 i.e. previous date and for some reason this fails.kindly see my script... (2 Replies)
Discussion started by: bigtejus
2 Replies

8. Shell Programming and Scripting

awk subtraction

hi i have file 1 as follows: 6 7 8 9 10 i have file 2 as follows: 5 5 5 5 5 i want file 3 as follows: (4 Replies)
Discussion started by: npatwardhan
4 Replies

9. Linux

date subtraction(URGENT)

Hi all, I need the date subtraction fuctionality using shell commands. For example: date1:Wed Apr 5 08:35:21 IST 2006 date2:Tue Apr 4 10:35:44 IST 2006 I need the date subtraction result like " 22 hours 23 seconds". Please guide me to complete this task. Can you please help me ASAP. ... (3 Replies)
Discussion started by: uday123
3 Replies

10. Shell Programming and Scripting

Date Subtraction in KSH

I need to figure out the numeric representation of the previous month (in an automated monthly-running script) so that I may append it to a filename. I have tried statements such as variable=`date +%m -1` (and several variations) but with no success. I have also tried simply assigning the value... (3 Replies)
Discussion started by: mharley
3 Replies
Login or Register to Ask a Question