Sponsored Content
Top Forums UNIX for Dummies Questions & Answers Need to understand shell script Post 302867953 by Corona688 on Friday 25th of October 2013 10:57:46 AM
Old 10-25-2013
. means 'run this program inside your own shell'. This allows it to set variables inside your shell, which wouldn't be possible if you ran a script with ./scriptname -- when you create a new process its variables are separate.
This User Gave Thanks to Corona688 For This Post:
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

bash shell: 'exec', 'eval', 'source' - looking for help to understand

Hi, experts. Whould anybody clear explay me difference and usage of these 3 commands (particulary in bash) : exec eval source I've tryed to read the manual pages but did not get much. Also could not get something useful from Google search - just so much and so not exactly, that is... (3 Replies)
Discussion started by: alex_5161
3 Replies

2. UNIX for Dummies Questions & Answers

Help required to understand a variable in shell script!!!

Hi, I need to understand the following script: a=`dirname $0` b=`uname -s` if ; then c=$a/../../../platforms/$b/extlib else c=`pwd`/$a/../../../platforms/$b/extlib fi There are a bunch of variable assignments going on here!!! What does this variable means: "${a:0:1}" ... (2 Replies)
Discussion started by: abhishek2301
2 Replies

3. Shell Programming and Scripting

I need to understand the differences between the bash shell and the Bourne shell

I do not claim to be an expert, but I have done things with scripts that whole teams of folks have said can not be done. Of course they should have said we do not have the intestinal fortitude to git-r-done. I have been using UNIX actually HPUX since 1992. Unfortunately my old computer died and... (7 Replies)
Discussion started by: awk_sed_hello
7 Replies

4. Shell Programming and Scripting

Understand a old unix shell script

Hi All, I have a unix old script i but i am not able to understand the few commands in it and what it does. below is the script. if ; then for F in $(find $DIR/. ! -name . -prune -name "DP_*.dat") do IN=${F##/*/} OUT='ORD'$(echo $IN | cut -c7-) exec.ksh $IN... (2 Replies)
Discussion started by: kam786sim
2 Replies

5. Shell Programming and Scripting

Need to understand a couple of Shell Logic

Hi, I am trying what the following loop does : for i in XYZ do for j in M1 R1 R2 R3 do if then kList="" n=1 while do kList="$kList $n" let n++ done There are a couple of loop as mentioned above for R1.R2.R3. (1 Reply)
Discussion started by: johnprince1980
1 Replies

6. UNIX for Dummies Questions & Answers

Help with understand shell script coding

Good afternoon everyone, I am very new to UNIX shell scripting and I am trying to understand the following code. I know what it does but I need to modify it so it will allow me to pass a file name as *FILENAME* Thank for any guidance offered. if ] ; then match=`expr "$file" :... (2 Replies)
Discussion started by: Walter Barona
2 Replies

7. Shell Programming and Scripting

I am learning shell scripting and i would like to understand how sort -k3,3 -k 4,4 short* works

Please help me understand how sort -k3,3 -k 4,4 short* works , is it sorting 3 and 4 th field ? what is the use of specifying 3,3 and 4,4 in sort and what is actually does and i see sort -k3 short* and sort -k3,3 -k 4,4 short* giving the same output. Sort output attached Please help (2 Replies)
Discussion started by: Antony Ankrose
2 Replies

8. Shell Programming and Scripting

Need to understand how the line in perl program works as shell commend

I have a file with two line, one is header, the other actual value: TYPCD|ETID2|ETID|LEG ID|PTYP|PTYP SUB|TRD STATUS|CXL REASON|CACT|CACTNM|ENCD|ENC D NM|TRDR|ASDT|TRDT|MTDT|STDT|LS|SECID|SECID TYP|SECNM|PAR|STCC|MARKET PRICE|DIS MARKET PRICE|MARKET PRICE CURRENCY|SRC OF SETTLEMENT... (2 Replies)
Discussion started by: digioleg54
2 Replies

9. Shell Programming and Scripting

Need help to understand the below shell script

Please help me to understand the below 3 lines of code.execute shell in jenkins 1)APP_IP=$( docker inspect --format '{{ .NetworkSettings.Networks.'"$DOCKER_NETWORK_NAME"'.IPAddress }}' ${PROJECT_NAME_KEY}"-CI" ) 2)HOST_WORKSPACE=$(echo ${WORKSPACE} | sed... (1 Reply)
Discussion started by: naresh85
1 Replies

10. Shell Programming and Scripting

How to understand special character for line reading in bash shell?

I am still learning shell scripting. Recently I see a function for read configuration. But some of special character make me confused. I checked online to find answer. It was not successful. I post the code here to consult with expert or guru to get better understanding on these special characters... (3 Replies)
Discussion started by: duke0001
3 Replies
UPSRW(8)							    NUT Manual								  UPSRW(8)

NAME
upsrw - UPS variable administration tool SYNOPSIS
upsrw ups upsrw -h upsrw -s variable [-u username] [-p password] ups DESCRIPTION
upsrw allows you to view and change the read/write variables inside your UPS. It sends commands via the server upsd(8) to your driver, which configures the hardware for you. The list of variables that allow you to change their values is based on the capabilities of your UPS equipment. Not all models support this feature. Typically, cheaper hardware does not support any of them. Run upsrw with a UPS identifier to see what will work for you. OPTIONS
-h Display the help message. -s variable Specify the variable to be changed inside the UPS. For unattended mode such as in shell scripts, use the format VAR=VALUE to specify both the variable and the value, for example: -s input.transfer.high=129 Without this argument, upsrw will just display the list of the variables and their possible values. Some variables are strings, and can be set to any value within the length limit. Others are enumerated types and can only be set to one of those values. Others may be within an allowed range of values. Refer to the list to know what's available in your hardware. -u username Set the NUT username for the connection to the server. This is optional, and you will be prompted for this when using the -s option if you don't specify -u on the command line. NUT usernames are defined in upsd.users(5), and are not linked to system usernames. -p password Set the password to authenticate to the server. This is also optional like -u, and you will be prompted for it if necessary. ups View or change the settings on this UPS. The format for this option is upsname[@hostname[:port]]. The default hostname is "localhost". UNATTENDED MODE
If you run this program inside a shell script or similar to set variables, you will need to specify all of the information on the command line. This means using -s VAR=VALUE, -u and -p. Otherwise it will put up a prompt and your program will hang. This is not necessary when displaying the list, as the username and password are not required for read-only mode. DIAGNOSTICS
upsrw can't set variables on your UPS unless you provide a valid username and password. If you get "access denied" errors, make sure that your upsd.users(5) has an entry for you, and that the username you are using has permissions to SET variables. HISTORY
This program used to be called upsct2, which was ambiguous and confusing. SEE ALSO
upsd(8), upscmd(8) Internet resources: The NUT (Network UPS Tools) home page: http://www.networkupstools.org/ Network UPS Tools 05/24/2012 UPSRW(8)
All times are GMT -4. The time now is 07:15 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy