Bash subtract dates. Here's what I've tried: .

Bash subtract dates How to write a query in SQL Server? I have this but doesn't work (it says "Operand data type is invalid for subtract operator") select CONVERT(DATE, GETDATE()) - CONVERT If (end date – start date) in days < 7 days then query end date = query start date + (end date – start date) in days else query end date = query start date + 7 days The query start date initially starts at 12 months ago and then is incremented within each loop cycle by the 7 days or whatever days are left going by the statements above. 2019 23:29:40 B= 05. stat -c%Y aggregator. Afterward, the program uses the -d option once more with the parameter “next week” to show @Ethan: It does work. $ echo 'scale=4;3. Any suggestions, recommendations will be much appreciated. @don_crissti, wrong dup. If you have GNU utils, there The following computes the difference of timestamps in minutes: printf '%d\n' $(( ( $(date -d 'tomorrow 00:00' '+%s') - $(date '+%s') ) / 60 )) Note the use of format string %d\n. The difference between 1980/1/1 and 1975/1/1 on the other hand is the ten years between epoch and 1980, minus the 5 years between 1975 and epoch. You might want to think about timezones and daylight saving. !#/bin/bash MEMFILE=lock The same without the I want to subtract months from a given date. date -v +1d This will give (current date +1) means 1 day after. Since Bash 4. Simple extension to answer the general question. 9k 13 13 gold badges I have two date/time values in yyyymmddhhmmss format in shell variables. Similarly below written code can be used in place of d to find out year,month etc. You can always capture the year with date +'%Y'. Or does bash have another w Convert each date to unix time using date -d "2019-01-01 "+%s. csv file. How do I convert each of these dates into epoch seconds? 7/21/17 6:39:12:167 GMT 7/21/17 6:39:12:168 GMT 7/21/17 6:39:12:168 GMT Skip to main content. Hot Network Questions Solana Program Deploy Tips Does light travel in a straight line? If so, does this contradict the fact that light is a wave? What type of valve has a screwdriver slot and no handle? Does gravity from a star go through a black hole's event horizon to affect objects on the other side I have a number, lets say it is 20160823130001 which stands for 2016 august 23rd 1300 hrs 1 second. How do I get the difference between two dates under bash [duplicate] (3 answers) Closed 3 years ago. I'm aware of date --set="2013-07-10"+%T (or something like this). The advantage of bc is that it supports arbitrary precision while shell arithmetics is limited to the processor's double I need to compare two dates/times using Bash. 2 how subtract 10 minutes from a timestamp, not the current Bash supports == as an extension, but that'll bite you when someone tries to run your code with /bin/sh on a platform using ash or dash; BASH Array indexing minus the last array. Modify date of a file to be older that any other file in a certain folder. If you have GNU date (that's a big if if you really want My goal is to run the shell script without having to increment the calendar day each morning. How can I subtract two dates in epoch format using Shell Scripting. 005 1. 1. It should work in most POSIX-compliant environments unless otherwise specified. 0 21. 56. I would like to subtract the values of column 2 and 4 and need to create a new column to the output. Month: / Day: / Year: Date: Today. From that number I need to add or subtract 10 mins and I cannot figure out how to do it in bash. fiveminutesbefore=$((timestamp - 5 * 60 * 1000)) This uses arithmetic expansion to subtract 5 lots of 60 (seconds in a minute) lots of 1000 (milliseconds in a second) from your value timestamp, giving a time five minutes earlier as you would expect. I have to subtract current date from a given date to get number of days as a difference. (script to subtract a future date from a current date) Please how do you write this script out? so far i have: date -d '12/7/20' +%j 342 <- that was the output Hi, I have one . SECONDS Each time this parameter is referenced, the number of seconds since shell invocation is returned. 1. Fine. How I substract 2 timestamps using shell scripts . n days ago from a given date on command line. Try Teams for free Explore Teams Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. What is the correct syntax? #!/usr/bin/env bash FIRSTV=`ls -1 | wc -l` cd . 012 1. co1 co2 co3 co4 r1 15. Example: 2012-11-19 - 1 month = 2013-10-19 This one doesn't work: d I want to subtract two columns They have these formwithout decimals 1. The input format of date is like this : 20130101 which means 01 January 2013 I use this command to accomplish that: date -d "20130101 @SirBenBenji, that said, %1 is a job control construct, and job control is turned off in noninteractive scripts unless you explicitly turn it on yourself. With date, how to specify a relative date when the specified date contains hours/minutes/seconds. date command could understand months in the format of strings through the strptime(3) libc function. bash: How to compare two dates on Solaris without date -d option. You can do that by first by converting the nanosecond value in EPOCH to seconds value in EPOCH and then use that for conversion to human readable strings How to subtract a set from another in Bash? This is similar to: Is there a "set" data structure in bash? but different as it asks how to perform the subtraction, with code. 2018-03-20 21:00:00 -> 2018-03-20 14:00:00 2018-03-20 06:00:00 -> 2018-03- Skip to main content. Look to convert to some -s (seconds since 1970) value, and subtract 24*60*60 seconds from that value. How to iterate through dates from start date to end date? 1. comments sorted by Best Top New Controversial Q&A Add a Comment Ok, I have a cron job to record an internet radio show that I enjoy. Wake me up when September ends. 000 900 1. Bash: How can I subtract two time strings using bash? 3. Later, it prints the day before yesterday using the -d option along with the given parameter “-2 day“. Bash script - convert time according to template. mathematical. eg. Skip Subtract days from a date in Bash. Timestamp Subtraction Using Bash-Utils. I have tried to convert date time in I have two time strings; eg. How to grave the Date from this command in bash script. I am trying to subtract date column 2 from date column 3. 2, printf has a new modifier %(dateformat)T that, when used with argument -1 outputs the current date with format given by dateformat, Subtract two What is a fast way to subtract two lists1. date --date '2017-08-17 04:00:01' +%s # "1502938801" And this will give you the date as a readable string from a number of seconds. Can't set time to wee hours of The output when using +%s is the number of seconds since the Epoch, so you can use $(( $(date +%s -d "later") - $(date +%s -d "earlier") )) in Bash to calculate the number of seconds between later and earlier. 30. For whole days, I usually force the times to 12:00:00 which avoids most of those issues. And, particularly, the -d option (that allows to use the date specified instead of the current date that date is supposed to use otherwise, when used in "print the date" mode) is not common to all "date". The date command in Bash is used to display and format the current date and time of the system. For example, Tue Jul 11 12:14:01 PM +06 2023 See the following output, when the date command is run in the Ubuntu terminal:. Find difference between two dates in bash. Enter a start date and add or subtract any number of days, months, or years. bed The input is: Different Formatting Options. Improve this answer. Viewed 437 times 0 Lets say I have below two variables. 10. Calculate difference between two I am working on bash. I will subtract the num2 from the num1 variable utilizing the arithmetic expansion $(()) and print the result on the More Related Answers ; bash date today plus one day; bash date one year ago; date linux minus 1 day; bash do multiple times; bash get timestamp; bash count elapsed time in seconds It is a string in bash and I want to get it converted into a date so that all other date functions can be used on it. bash doesn't have a date type. What are these "all other date functions" you're talking about? – Thomas. I want to calculate the difference in time by passing in a string HH:MM value to set the time and calculating the difference between this and the current system time. Here's what I've tried: How to subtract days in dates ? Do I need to separate time and date or is there a way to subtract the data in this way ? I really appreciate any help. The lists may be small, maybe a direct way in shell works. Commented Apr 21, 2017 at 4:07. However, picking out that date field and reordering the fields as yyyy-mm-dd makes it much easier, and sort can handle this as a standard alphanumeric sort. For example, `2003-07-31 -1 The image shows that the Bash script has subtracted the num2 variable from the num1 variable and then printed the result on the terminal. Add a comment | 21 Answers Sorted by: Reset to default 701 . I ask, what do you want I am working on bash. One of the files has a mistake though so I would like to take that out of the folder and rename the following ones such that I still have them all sequential without any gaps in the numbering. I have two time strings; eg. The formatting option allows you to format the date in different ways or get just Date Calculator: Add to or Subtract From a Date. Follow edited Feb 21, 2012 at 5:14. 280 is milliseconds. Is there a way in unix to subtract a month or at least 30 days from a specific date? The date is to be inputted by the user. Also It should work even for more than 12 months ( as I You can use the following syntax to subtract a specific number of days from a date in Bash: new_date="$(date -d "$my_date - 10 days" +%Y-%m-%d)" This particular example Let’s see a couple examples of how to subtract time from a current date using date string. date [-jRu] -f input_fmt new_date [+output_fmt] []-f Use input_fmt as the format string to parse the new_date Subtract months from a given date in bash. I want to subtract one from the other and get the result in seconds like below: a=20170804020000 b=20170804015959 c=a-b The result I want is c=1 (because 02:00:00 is one second later than 01:59:59), but I got c=4041. For example, it might appear in application log files, like this:: This article explains how to subtract one time from the other in Bash, and obtain the intervening time in seconds. function gendates { for dd in $(seq -w $1 $2) ; do date -d $dd +%Y%m%d 2>/dev/null ; done ; } date and bash can do date differences (OS X options shown). 0. Date conversion and subtraction in shell script. s1="Fri Sep 10 22:24:51 IST I have a date in the variable x=20170402, getting this value from another file. Asking for help, clarification, or responding to other answers. new_epoch_time=$(date -d "+60 seconds" +%s) To subtract seconds, you can use the -operator. The date command prints the current date and time in the following format by default: ‘Weekday_name Month_name Day_of_month Hour:Minutes:Seconds AM/PM Timezone(HH) Year’. How to add time to a date variable in linux? 0. By using these commands, you can easily calculate All the other questions on the SE network deal with scenarios where either the date is assumed to be now (Q) or where only a date is specified (Q). echo $((($(date -jf%D "04/03/16" +%s) - $(date -jf%D "03/02/16" +%s)) / 86400)) # 31 Method 1: Calculate Difference Between Two Dates. Also It should work even for more than 12 months ( as I came across few which were . Adjusting the 'date' command to subtract three hours. Bash has a handy SECONDS builtin variable that tracks the number of seconds that have passed since the shell was started. Example container1-last-deploy. However, I've having issues with the systax. Bash – Date format; Bash – Get current year; Bash – Get current month; Bash – Get current weekday; Bash I have some text files as shown below. This can be useful in various scenarios, such as calculating the number of days between two events or determining the age of a person. Later the echo command is used to print yesterday’s date that was saved in the ‘yesterday’ variable. Example: 2012-11-19 - 1 month = 2013-10-19 This one doesn't work: d Skip to main content. Repeat: Calculate times. 2019 01:15:52 I want to perform a arithmetic operation C = A - B using bash. This particular example calculates the number of days between the date stored in the $date1 variable and the date stored in the $date2 variable. 7. 3. I recommend we don’t use java. Bash – How to Get Future Date and Time. [] The date string format is more complex than is easily documented here but is fully described in the info documentation. The usual method would be to convert both Edit: I have seen that the date command is indeed the right way to go, however I seem to be getting issues whenever I pass array variables through subtraction with date. About; Products OverflowAI; Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & Understanding Different Date Formats. coffee. Commented Apr 25, 2017 at 12:18. Example: Current date Last used date '2016-03-30' '2015-02-03' Current date refers to today's date, "Last used date" is a measure. In the How can I subtract two dates in epoch format using Shell Scripting. Date is not a built-in command from bash. If they click the 'prev' button then it should become Subtract time using date and bash. you're just showing p-code here so you won't really be calling "functions", you'll be submitting special args to date. 020 1. "20121212" string into "20121212" date . command to Substract two timestamps in unix. 11. 1415+9. Amount of X day increments from date. That one if for non-GNU solutions while I suppose alpine linux is a GNU system. Convert "Thu Sep 22 3:50 2016" to "2016-09-22" in Solaris, without GNU date. date --date '@1502938801' # "17 Aug 2017 04:00:01" So all that's needed is to convert your date/timestamp into a format that GNU date can understand, use maths to determine the difference, and output the result I want to find out total system boot time by subtracting two timestamps. The difference between 1980/1/1 and 1960/1/1 is the ten years between epoch and 1980, plus the 10 years between 1960 and epoch. 33. Example 3: Calculating the Difference Between Two Dates. I figured out that date in BASH retrieves the current date. Includes syntax, examples, and best practices for reliable arithmetic operations. How to generate sequential dates/times in a shell script? 1. MS, I can read and print all of the saved Timestamps but when I do some arithmetic operation like Subtract (say Timestamp2 - Timestamp1) it doesn't give me the answer, I do not have experience work with bash script programming. 4. This function gendates generates a list of valid dates between two dates in YYYYmmdd format (oldest first). example: [yyy-mm-dd] - 30 days 2011-07-23 - 30 days By the way, the date can be any date depending on the user input. How do I wrap a timezone adjustment to the date command in a string? 1. Get the EPOCH time for the date in question: EPOCH=$(date -d 'Thu Dec 19 14:10' '+%s') This gives you the time, in seconds, since the EPOCH (typically 01/01/1970) Now you can use simple math to subtract or add 5 minutes (in seconds) to the EPOCH time Ask questions, find answers and collaborate at work with Stack Overflow for Teams. Can some one help me in converting them into integers. Set the variables accordingly for your needs and then adjust the logic as need for your needs as well. 07. Viewed 912 times 1 I've been trying to get a string to output each character individually on the same line (with a fancy gradient effect in bash), although something in the subscripting part isn't working out quite right: Here the -d command option is used to get yesterday’s date. Shell script cUrl command with URL being a variable. dat. How to I have a two variables : A= 04. However I am not successful head_info: 05-31-2017:04:27:37 tail_info: 05-31-2017:04:30:57 the problem is that In a bash script, if I have a number that represents a time, in the form hhmmss (or hmmss), what is the best way of subtracting 10 minutes? ie, 90000 -> 85000 How to subtract values of two columns and add to a new column in text file using awk/bash script Hot Network Questions What it’s like to be supervised by an professor with other priorities Note the remark from William Pursell above: this solution is dependent on your "date" version. Shell - Subtracting an integer from a date. Your dates include fractions of seconds. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online In Bash, you can also use the magic variable SECONDS:. I need to calculate how many days exist between 2 dates. Bash: How can I subtract two time strings using bash? 0 How can I subtract timestamp results from `date` in one line of shell? 3 How to subtract 5 minute from date. Hot Network Questions Historically, comparing dates in shell scripts wasn’t straightforward due to different date formats and lack of built-in functions. Subtract them and convert the result to the desired format. Note that this will not work on all date variants; it will only work on GNU date, as far as I know. I'm trying to figure out how I can use AWK to subtract lines. Divide by 86400 to get days. How do I subtract the value of column 2 of one row with the value of column 3 of the previous row and print the result in a new row in bash. I want to let users easily add and subtract dates using JavaScript in order to browse their entries by date. The time should be added. using gnu date to set a time and format and subtract. lock Consult man stat for a complete list of the data you can get about a file, and the corresponding format (-c) codes. bashrc equivalent for sh. r; Share. r/bash. This variable retains its properties when assigned to, Example: How to Add and Subtract Days from a Date in Bash This article is currently being written on August 20, 2024. Hot Network Questions Is it possible to travel to USA with legal cannabis? Driveway electric run using existing service poles decode the pipe How to reproduce this equation itemization? Find the radius of a circle given 2 of its coordinates and their angles. How can i do this? ex: if i subtract one day, y=20170401; two days, y=20170331 and it is GNU based. The fuzz in units can cause problems with relative items. The given date is in format m/d/yyyy so instead of 09/26/2015 it is 9/26/2015. What I was trying to do is convert it to EPOCH time, subtract and then divide by 84600 to get the number of days between the two dates. Ask Question Asked 8 years, 3 months ago. You can probably guess the meaning of the formatting symbols I used: %Y is for year %m is for month %d is for day and so on; You can find this, and other formatting symbols in man date. You can subtract 1 with the POSIX arithmetic operator, e. Commented Jul 9, 2014 at 17:33. Add/Subtract: Years: Months: Weeks: Days: Include the time. Playing with dates in bash: passing variables. There are various aspects to compare dates in Bash, from simple comparisons to advanced scenarios including date arithmetic and UNIX timestamps. 2,711 17 17 silver badges 15 15 bronze badges. The dates are in the format: "mm/dd/yyyy". Modified 8 years, 3 months ago. Calculate the difference between two timestamps in bash. I also figured out that I can add X days to the current date in the following way, expiration_date=$ date -v +1d which gives, Tue Sep 26 20:28:13 CEST 2017 Subtract days from a date in Bash. Date, though. In Bash scripting, it’s a very common task to calculate the difference between two dates for scenarios such as schedule management, tracking duration, If you have stat (which is part of the GNU coreutils package, so you should find it on any GNU/linux system), then you can get the modification time of a file directly in seconds:. Subtract time using date and bash. So even if I try to convert both dates into same To subtract dates in a shell script using bash, you can use the date command to convert the dates to Unix timestamps, subtract them, and then convert the result back to a human-readable format. Subtract big number in bash. Subtract hours from date object in bash. Improve this question. How to compute a relative date from a given date? 1. The problem is that date takes your request quite literally and tries to use a date of 31st September (being 31st October minus one month) and then because that doesn't exist it moves to the next day which does. Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. #!/bin/bash # Time Arithmetic TIME1=05:36:11 TIME2=06:46:00 # Convert the times to seconds from the Epoch SEC1=`date +%s -d ${TIME1}` SEC2=`date +%s -d ${TIME2}` # Use expr to do the math, let's say TIME1 was the start and TIME2 was the finish DIFFSEC=`expr ${SEC2} - ${SEC1}` echo Start ${TIME1} echo Finish ${TIME2} echo Took ${DIFFSEC} From the info page for gnu date: Our units of temporal measurement, from seconds on up to months, are so complicated, asymmetrical and disjunctive so as to make coherent mental reckoning in time all but impossible. So even if I try to convert both dates into same Subtract days from a date in Bash. 8. For example, to subtract 60 seconds from the current epoch time, you can use the following command: In addition to the date command, Bash also offers a range of arithmetic and string manipulation operators that can be used to perform calculations and We tested the code in this tutorial on Debian 11 (Bullseye) with GNU Bash 5. Following command works for me to generate the value in bash file: date +%s000. bash; date; macos; arithmetic; date-utility; Share. Stack Overflow How to subtract values of two columns and add to a new column in text file using awk/bash script. What I want to do is 4 Examples to Compare Dates in Bash Using If Statement. But I cannot figure out how to set the time part to be the string HH:MM value that I pass in and leave the data as the current date. awk question - how print additional lines only for unique dates. 2. Provide details and share your research! But avoid . 2 13. How to Subtract a Date value in a variable. How to subtract two different date formats to get days in bash? 0. GNU date will to the math for you:. Hot Network Questions How to teach high school students to analyze diagrams in a proof? PSE Advent Calendar 2024 (Day 18): A sweet & short expected chemistry Christmas puzzle Listing Subtract time using date and bash. Subtracting Times. So December 31 - 1 month is December 1, not a day in November, and March 31 - 1 month is March 3 (unless executed in a leap year). Some common date Note that while bash doesn't support floating point arithmetics with $(()), many shells (ksh93, zsh, yash at least) do. Add hours to the date and time. Need some There isn't an easy way to sort the date field ([d]d/mm/yyyy) directly within a comma-separated field (sort natively understands US mm/dd/yyyy style dates but not this international alternative). 280 where . How can I increment a value in a bash script I have some a folder with enumerated files with names such as FILE_001. The proper way to refer to individual subprocesses inside a script is by PID, and even then, waiting for processes to complete is automatic unless they're explicitly backgrounded by your code (as with a &), or Easily Add or Subtract Days from a Date with a Windows Batch Script. In gene I have a script where i’m trying to get the start date and end date of last 18 months ex. Include only certain weekdays. While writing the shell scripts, I realise that sometimes we are required to find future dates—for example, dates after 10 days, 2 months, or 1 year, etc. In Bash, you can easily calculate the difference between two dates. Hot Network Questions A variant of the law of total probability Is Instant Reload the only way to avoid provoking an attack of opportunity while reloading a projectile weapon? Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. date --date "7 days ago" Other version will require you to covert the current date into seconds since the UNIX epoch first, manually subtract 7 days' worth of seconds, and convert that back into the desired form. g. Here I have two variables named num1 and num2. Go to bash r/bash. Learn how to perform subtraction in Bash scripting with various methods like arithmetic expansion, expr, let, and bc for floating-point numbers. I want to modify this by adding/subtracting and save to new variable. Subtracting two timestamps in bash script . MacOS date - convert date string to seconds since Epoch. 4. . bash shell scripting: create an endtime from a starttime. shell script that includes a message that says how many days are left in a semester. Or the lists may be long, maybe external tools are the faster way. Subtracting two timestamps in bash script. I have 2 date columns present in file, column 2 and column 3. $ expr $(date +%Y) - 1 2016 (note: with expr you must leave a space between the math operator and the values) How subtract days from date in bash shell on Solaris 11? 0. 012615 15150000001 0. Here is an example code snippet to subtract two dates in bash: I have a file that contains a set of Timestamps in format of H:M:S. Place the latter date first. Here's quote from the info page for Gnu date (which is the date version which In order to get 1 day back date using date command: date -v -1d It will give (current date -1) means 1 day before . How can I subtract date/time values to have result in How to subtract values of two columns and add to a new column in text file using awk/bash script Hot Network Questions Why does adding and deleting a character with nano to an executable in /bin yield a segfault? I realize there are tons of questions and answers involving date calculation, but I haven't found a solution to the issue on OS X/macOS. Ask Question Asked 8 years, 5 months ago. string to date in shell script; bin bash date save file; add one day to timestamp; how to check date is older than x days in shell script; bash week day - work day; how to view day in shell; bash subtract dates; simple bash prepend timestamp to output; bash date as d/m/y; bash date as d/m/y; Write a shell script to print current month nd year I want to subtract 2 dates in MS SQL Server. I want the output in Months, Days, Hours format. alg4: join -v on sorted lists (Thanks @Kusalananda) alg5: comm (Thanks @Stephen Kitt) alg6: zsh (Thanks @Llua) As man date says near the top, you can use the date command like this: date [OPTION] [+FORMAT] That is, you can give it a format parameter, starting with a +. Uppercase variable names are reserved for environment variables, and it is recommended to use lowercase instead for your own variables. So I decided to get fancy and write a cron job to remove the old shows. How to subtract 2 numbers in 2 different files? Hot Network Questions No bubble formation in hot water In linux bash shell, how to subtract a variable from another in if? I've tried the following: I've tried the following: #!/bin/bash start=0 end=1 if [ end - start -eq 1 ]; then echo "right" fi #!/bin/bash # Time Arithmetic TIME1=05:36:11 TIME2=06:46:00 # Convert the times to seconds from the Epoch SEC1=`date +%s -d ${TIME1}` SEC2=`date +%s -d ${TIME2}` # Use expr to do the math, let's say TIME1 was the start and TIME2 was the finish DIFFSEC=`expr ${SEC2} - ${SEC1}` echo Start ${TIME1} echo Finish ${TIME2} echo Took ${DIFFSEC} seconds. util. This would be easy if it was 1330 hrs but since it is 1300 it needs to end up as 1240 and 1310. Subtract 10 years from a current date: $ date Tue Jul 13 21:12:52 EDT 2021 $ date - Convert both timestamps with GNU date to seconds since 1970-01-01 00:00:00 UTC. Ask questions, find answers and collaborate at work with Stack Overflow for Teams. In Bash, you can also use the magic variable SECONDS:. Bash variable assignments must have no spaces, as in val=x, and not val = x. Here's a solution I came up with for calculating date (add or subtract) with a batch script. That class is poorly designed and long outdated. Try Teams for free Explore Teams Supposing your timestamp is in a variable timestamp, and in milliseconds since the epoch:. For example for the input file, i would like to have something like this: 0. Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site The same thing can be done from the command line using the lowly date command, possibly with a little help from Bash's arithmetic. Skip to main content. ) Subtract months from a given date in bash. How to calculate the previous month and year from string in Bash. 018029 15150000000 0. 13. To bash how subtract characters from string. Previous day date in unix shell script. I don't have macos so I can't test my answer, but according to macos date man page:. Getting date of X days ago in bash script, using argument variable. You shouldn't pass your data in the first argument for printf, as the first argument is the format string, and printf may interpret some sequences as the format specifiers (%d as integer specifier, %s I have time format 2020-01-06 11:27:12. The --date=STRING is a mostly free format human readable date string such as "Sun, 29 Feb 2004 16:21:42 -0800" or "2004-02-29 16:21:42" or even "next Thursday". txt: This is for bash on macos, preferably a bash 3 solution. How do I calculate the time difference in minutes between these two? Can the standard date library do this? Ex From man date. 4 r2 23 Subtract 2 array values having floating point decimals Hot Network Questions Alternative (to) freehub body replacement for FH-M8000 rear hub Bash Shell Current Date Minus Number of Days. 010 1. 007046 15150000002 0. The Linux date command I wanted to add one day to a date in bash using date command. I'd like to subtract the last deploy date, from the current date and then write to a file if the last deploy date is greater than 2 months. no, Start_date,End_Date 1, 7/29/2012,10/27/2012 2, (9 bash convert seconds to date; java date minus 1 day; days between two dates in Linux; how to calculate duration of time in shell script; bash subtract dates; linux reboot every day; bash get date n days future; date linux minus 1 day Comment . The same thing can be done from the command line using the lowly date command, possibly with a little help from Bash's arithmetic. Add a comment | Your Answer subtraction in bash doesn't work. – roblogic. 99' | bc 13. First I use this command to get the start time and end time: sudo journalctl | grep "Logs begin at" | awk '{print $6" "$7" "$12" "$13}' The existing answer is pure bash, so it will be faster than this, but it can only handle integers. awk '{a=$3; b=$2; c=a-b;print $0,c;}' input. Hm. Eg: my file look likes s. $ echo $(($(date +%Y) - 1)) 2016 You can also use the POSIX compliant expr math operators, e. Share. Bash relies on this date command to compare and manipulate dates. 015 1. "09:11" and "17:22" on the same day (format is hh:mm). I tried with awk like this, but I miss the part to change the line. txt mentioned in the script is older than the specific date meaning that it was created before the given date. Subtracting times obtained from date: #!/bin/bash startdate=$(date +%s) sleep 130 enddate=$(date +%s) timetaken=$((enddate-startdate)) printf 'Total downtime was %d Use unix time instead, date +%s, then subtract to get the difference in seconds. Method 2: Calculate Calculating the difference between two dates in Bash can be done using different commands, such as ‘date’, ‘bc’, and ‘awk’. The formatting option allows you to format the date in different ways or get just Subtract days from a date in Bash. However I manually end up having to go and delete these recorded shows. Commented Oct 17, 2019 at 10:57. Possible duplicate of Tool in UNIX to subtract dates – don_crissti. Hot Network Questions How to define a specific electrical impedance symbol in Circuitikz: a rectangle filled with diagonal red lines at equal intervals? Project Hail Mary - Why does a return trip to another star I am trying to get the time difference between two dates as given below in Bash script. Upgrade Alpine Linux system with no internet connection. Copy bash array to a variable which name is hold by another variable. Popularity 8/10 Helpfulness 9/10 Language If you're using bash under linux, you can use the -d parameter to perform date manipulation on an existing date:. How do I calculate the time difference in minutes between these two? Can the standard date library do this? Ex You need to subtract 5 minutes from a known point in time: $ date -d "00:00:00 today" Thu Oct 8 00:00:00 EDT 2015 $ date -d "00:00:00 today -5 minutes" Wed Oct 7 23:55:00 EDT 2015 You just need to add your format string. This considers only whole seconds. (Oh, and local is also a reserved word. y-Year, m-Month w-Week d-Day H-Hour M-Minute S-Second Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. I would like to calculate the time difference between two dates and times, but I must have the syntax incorrect. Instead, the shell will take the current day and subtract one calendar day and then load that date within the url. Stack Overflow. Example 02: Subtract Two Variables Using Arithmetic Expansion. The date command, with %s to convert dates to seconds since the Unix epoch (00:00:00 UTC on 1 January 1970), is a godsend. I want them to be able to click a "Next" button, and if the date is: " 06/01/2012" then on clicking next, it should become: "06/02/2012". 6 $ date +%s 1655894738 Once the date command has converted start and end dates to seconds, it’s easy to subtract one from the other and convert the result to the number of days between the two dates. Follow answered Jun 29, 2021 at 12:29. – tagg. By Rahul September 26, 2022 2 Mins Read. 5. BASH: subtract date to get a runtime. UNIX Epoch Timestamps Using this method, we can also subtract and compare dates in arbitrary formats as long as the date command or another tool of choice recognizes them. I convert it to seconds with startdate="$(date -d"$1" +%s)"; What I need to do is iterate eight times, each time Now I need to subtract 7 hours from that particular date and time. set1: N lines as output by a filter; set2: M lines as output by a filter; how to get: set3: with all lines in N which don't appear in M Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Current version of GNU bash is 4. Want to subtract 500 milliseconds from this time and get result in same time format again. - 1 month will subtract one from the month number, and then if the resulting date is not valid (February 30, for example), adjust it so that it is valid. Run both dates (against the 1970-01-01 epoch) with +%s, then subtract the seconds. is there a way to subtract a month from a date or at least 30 days in unix. This works very well for my needs and it's all contained to the same one batch Not only floating points, but also the spacing would lead to syntax errors. Using `date` with the `-d` / `--date=` option. Subtract date & time from current date & time in bash. The two most important features of the date command to understand for doing date math are the +FORMAT option and the --date option. See man bc for more information. So far, all the answers use the external program date. Both scenarios covered. That lets you simply write, for example: to subtract 60 from the value and echo that -- but of course, date arithmetic isn't that simple; subtracting 60 from 201908210012 will not produce 201908202312 like you would hope. We can use the following syntax to store this current date in a variable named my_date : I have a Bash script that takes an argument of a date formatted as yyyy-mm-dd. 3. The date documentation (from info date) has the following advice:. if april is the current month then the return start date should be 2022-10-01 and return end date should be I have the script below to subtract the counts of files between two directories but the COUNT= expression does not work. 010 I need another column in the Skip to main content. Then subtract the unix times. For example, imagine the input file is: 30 20 The output would be: 10 Now, as a test I am trying to calculate the "Used" memory column from: $ cat /proc/meminfo So at the moment I have written this: Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site This image states that the file file1. Unix time +n days on Solaris without date Is there a way in unix to subtract a month or at least 30 days from a specific date? The date is to be inputted by the user. But sometimes the date stamp will be 20160823125959. Commented Jun 21, 2012 at 18:25. In this article, we’ll discuss different methods to calculate the difference between two dates in Bash. businessDate='2019-12-31' diff=1 busDate=$ Is this an issue with the date function? I am not very familiar with bash. Hot Network Questions Why do some installers insist on not doing a full frame window replacement? The Linux date command displays the current date and time of the system. Count Days Add Days Workdays Add Workdays Weekday Week № Start Date. 012989 15150000003 It appears in many places on the system and is the default produced by the “date” command. unless your system has the GNU core-utils package installed, this is probably as good as you can do. 1315 The scale=4 tells bc to use four decimal places. – Hastur. I would like to subtract column 1 when column 2 is the same. Subtract days from a date in Bash. Modified 8 years, 5 months ago. Lyncean Patel Lyncean Patel. /etc/bash. Input format: 2014-12-01T21:34:03+02:00 I want to convert this format to int and then compare the ints of the two dates. Subtraction in bash. If you need to handle floats, you have to use the external program bc. Stack Exchange Network. alg3: processing an string in bash. xjjvx xhras evgjdkv jrow zzh gckqgw wclj ugbw cjivvqlz ogauk