Sponsored Content
Top Forums Shell Programming and Scripting Real-time scenarios where VARIABLE SUBSTITUTION/EXPANSION is useful Post 302946368 by Chubler_XL on Monday 8th of June 2015 06:14:50 PM
Old 06-08-2015
I tend to use ${variable%pattern} most frequently to remove extensions from filenames. Second most common usage is probably splitting up strings (date or time strings for example):

Code:
year=${date%%[/ -]*}
day=${date##*[/ -]}
month=${date#*[/ -]}
month=${month%[/ -]*}

 

5 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

sed insert command and variable expansion/command substitution

I know this script is crummy, but I was just messing around.. how do I get sed's insert command to allow variable expansion to show the filename? #!/bin/bash filename=`echo $0` /usr/bin/sed '/#include/ { i\ the filename is `$filename` }' $1 exit 0 (8 Replies)
Discussion started by: glev2005
8 Replies

2. Shell Programming and Scripting

[Solved] Command Substitution and Variable Expansion within a Case

Hello All, I don't write scripts very often, and in this case I am stumped, although it may be a bug in the version of bash I have to use (it's not my system). I want to extract a specific string snippet from a block of text (coming from a log file) that is dependent on a bunch of other... (1 Reply)
Discussion started by: jaimielives
1 Replies

3. Shell Programming and Scripting

Shell script to convert epoch time to real time

Dear experts, I have an epoch time input file such as : - 1302451209564 1302483698948 1302485231072 1302490805383 1302519244700 1302492787481 1302505299145 1302506557022 1302532112140 1302501033105 1302511536485 1302512669550 I need the epoch time above to be converted into real... (4 Replies)
Discussion started by: aismann
4 Replies

4. Shell Programming and Scripting

Converting real time to epoch time

# date +%s -d "Mon Feb 11 02:26:04" 1360567564 # perl -e 'print scalar localtime(1360567564), "\n";' Mon Feb 11 02:26:04 2013 the epoch conversion is working fine. but one of my application needs 13 digit epoch time as input 1359453135154 rather than 10 digit epoch time 1360567564... (3 Replies)
Discussion started by: vivek d r
3 Replies

5. Shell Programming and Scripting

sed variable expansion fails for substitution in range

I'm trying to change "F" to "G" in lines after the first one: 'FUE.SER' 5 1 1 F0501 F0401 F0502 2 1 F0301 E0501 F0201 E0502 F0302 3 1 F0503 E0503 E0301 E0201 E0302 E0504 F0504 4 1 F0402 F0202 E0202 F0101 E0203 F0203 F0403 5 1 F0505 E0505 E0303 E0204 E0304 E0506... (10 Replies)
Discussion started by: larrl
10 Replies
CAL(1)							    BSD General Commands Manual 						    CAL(1)

NAME
cal, ncal -- displays a calendar and the date of easter SYNOPSIS
cal [-jy] [[month] year] cal [-j] -m month [year] ncal [-jJpwy] [-s country_code] [[month] year] ncal [-Jeo] [year] DESCRIPTION
The cal utility displays a simple calendar in traditional format and ncal offers an alternative layout, more options and the date of easter. The new format is a little cramped but it makes a year fit on a 25x80 terminal. If arguments are not specified, the current month is dis- played. The options are as follows: -J Display Julian Calendar, if combined with the -e option, display date of easter according to the Julian Calendar. -e Display date of easter (for western churches). -j Display Julian days (days one-based, numbered from January 1). -m month Display the specified month. -o Display date of orthodox easter (Greek and Russian Orthodox Churches). -p Print the country codes and switching days from Julian to Gregorian Calendar as they are assumed by ncal. The country code as deter- mined from the local environment is marked with an asterisk. -s country_code Assume the switch from Julian to Gregorian Calendar at the date associated with the country_code. If not specified, ncal tries to guess the switch date from the local environment or falls back to September 2, 1752. This was when Great Britain and her colonies switched to the Gregorian Calendar. -w Print the number of the week below each week column. -y Display a calendar for the specified year. A single parameter specifies the year (1 - 9999) to be displayed; note the year must be fully specified: ``cal 89'' will not display a calen- dar for 1989. Two parameters denote the month and year; the month is either a number between 1 and 12, or a full or abbreviated name as specified by the current locale. Month and year default to those of the current system clock and time zone (so ``cal -m 8'' will display a calendar for the month of August in the current year). A year starts on Jan 1. SEE ALSO
calendar(3), strftime(3) HISTORY
A cal command appeared in Version 5 AT&T UNIX. The ncal command appeared in FreeBSD 2.2.6. AUTHORS
The ncal command and manual were written by Wolfgang Helbig <helbig@FreeBSD.org>. BUGS
The assignment of Julian--Gregorian switching dates to country codes is historically naive for many countries. BSD
November 23, 2004 BSD
All times are GMT -4. The time now is 02:31 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy