-- "$@" just means, "take the following arguments literally" and "all the following arguments, properly separated and quoted". If your arguments are "a b" "c d" "e f", "$@" will put them in as "a b" "c d" "e f", not "a" "b" "c" "d" "e" "f".
The 'shift' eats a commandline argument, i.e. converts $1=a, $2=b, $3=c, $4=d into $1=b, $2=c, $3=d. shift 2 moves it all the way to $1=c, $2=d. It's done since that particular branch uses an argument, so it has to remove two things from the list (the -r and the argument following it) not just one.
I have no idea why they're doing 'eval set', only theories. That's dangerous and dumb. They may be trying to process quotes inside quotes.
They are getting the values from 'getopt', the standard way to handle commandline arguments. I can't really explain its workings, but I'm sure others can.
Hi Corona688,
I agree wholeheartedly with your 1st three paragraphs.
But the "standard" way of handing command line arguments is getopts; not getopt. In the early days of the Bourne shell, there was a getopt utility that had problems dealing with quoted option-arguments and was replaced by the getopts utility that is in the current standards. The getopts utility is processed in a loop extracting one option and its option-argument (if there is one for that option) each time through the loop. The version in the standard doesn't have any provision for processing long options (i.e., --optionname or --optionname=argument), but many implementations of the getopts utility have extensions supporting them.
The standard getopts utility can handle command lines like:
producing identical results for any of the above. And, if operand1's 1st character is not a <hyphen>, will also recognize the following producing identical results to any of the above:
One might guess that the getopt utility called by the script in post #1 in this thread would normalize command line arguments splitting multiple option letters following a single <hyphen> into separate arguments each with its own <hyphen> and would split an an option with an option-argument presented as a single argument into two arguments so that the while loop in that script would work properly, but I have no idea whether the getopt actually being used by this application is this flexible.
Okay this is a mess, I'm trying to assign variables with variables in a for-loop. Here is what i have for code. The syntax is not good.
Given the following script:
#! /bin/csh
foreach site (ABC DEF GHI)
eval set \t$${site}sf = ``wc -l \$${site}.sf | awk '{print $1}'``
eval set... (2 Replies)
Hi All,
I'm running some encrypted data through a script I wrote. In order to do this, I'm using eval to resolve some of my variables. At the moment, when I use eval to resolve, it strips out some of my encrypted values, and totally drops some others. For example if I have the value ab1"3 it drops... (1 Reply)
first of all, thanks to all on this board, it has been a huge resource to answer most of my questions!
I am stuck on something that should really be simple, and was looking for some help.. I am using KSH on solaris and working on a script to move containers from server to server. Where i am... (4 Replies)
I am trying to expand the variable $user in my alias command and tried
several variations of eval but can't seem to get it to work.
The end result should be either:
oracle_user='sudo su - oracle ' or oracle_user='sudo su - oracle1 '
user=$(grep '^oracle:' /etc/passwd | cut... (5 Replies)
hi all,
Am trying to add some code to a ksh script and i dont understand how an eval function is used :
_var=$1
_conceal=$2
eval _val=\$${_var}
can someone shed some light on what the eval function in the above context means/does ??
thanks. (4 Replies)
Hi all,
some small script with eval turned me to crazy.
my OS is linux
Linux s10-1310 2.6.16.53-0.8.PTF.434477.3.TDC.0-smp #1 SMP Fri Aug 31 06:07:27 PDT 2007 x86_64 x86_64 x86_64 GNU/Linux
below script works well
#!/bin/bash
eval ssh remotehost date
eval ssh remotehost ls
below... (1 Reply)
Hi,
There is an Informatica tool through which unix scripts can be called. Now the requirement in my project is that a parent script calls a child script but this parent script has to be called through the Informatica tool.
In Parent script I'm using
TEMP=`getopt -o x:y: -l area:,volume:... (1 Reply)