There is an error when i am trying to use the shift command in this way:
($1 = -d, $2 = 123, $3 = -c etc etc)
for $arg in $@
do
case $arg in
"-d") shift; (so that the $2 will become the $arg now)
(and while it loop the 2nd time,)
... (1 Reply)
Hi Folks,
In shell scripting the maximum no. of command line parameters becomes 9(Am i right). If we want to get more than 9 parameters we use the shift command.
Even here there are two possibilities.
1. Without the use of variables - The arguments are lost and the lost no. is equal to the... (6 Replies)
I am running a program where in I have this command
which is giving error the shift: number is not correct.
can you please tell me how shift actually works?
the line which is giving error is-
set $PARAM; shift; shift; shift; shift; shift; shift; shift; shift
Is it related somewhere to... (2 Replies)
hi,
another perl question,
I don't understand the below
while (<FILE>) {
push @last5, $_; #add to the end
shift @last5 if @last5 > 5 ; #take from the beginning
}
can someone please explain to me how does
shift @last5 if @last5 > 5 is taking last 5 lines from... (5 Replies)
Hi,
I wrote one script, in between script needs to use 10th and 11th positional parameters, that time i used "shift". Here i am facing the below find problem,
./DataCount.sh: cannot shift
I tried
1) I have read man pages for shift
2) Before but * and **
3) Simple shift with out giving... (4 Replies)
Hey all, I need some assistance. I'm writing a script to eject tapes from a tape library, but the library is not a queued system and can only eject 15 tapes at a time.
I added paste -d : -s so that it goes through full_tapes and puts each media_id on one line separated by the :.
Now I'm... (2 Replies)
Hi,
Firstly, I did a search for this question both on this site and on the internet and have not been able to find a suitable answer that is not general in nature.
I have always been a Windows user. I use my girl friend's mac every now and then, but I always come back to windows. For a... (1 Reply)
Hello Expert
Can any one please explain what is the use of shift command in general terms:
set -- $(ls -t)
shift
rm -Rf $*
what is the use of shift command over here.
Thanks a lot for your help (2 Replies)
Hello everyone,
I am new to Perl and I am having some issues getting a script to work. I have to create a script that uses an array of 52 cards, "shuffles" the cards (using loops with the pop, shift, and push commands), and prints out the top five. This is not a randomizing of the array just a... (2 Replies)
#!/bin/bash
hostname=$1; shift
for hostname in $1
do
ping $hostname
done
I want to run the above script as hostname.sh yahoo.com google.com cnn.com. I want to shift each hostname to $1. How can do that with above code as currently it's not shifting. (5 Replies)
Discussion started by: scj2012
5 Replies
LEARN ABOUT REDHAT
foreach
foreach(n) Tcl Built-In Commands foreach(n)
__________________________________________________________________________________________________________________________________________________NAME
foreach - Iterate over all elements in one or more lists
SYNOPSIS
foreach varname list body
foreach varlist1 list1 ?varlist2 list2 ...? body
_________________________________________________________________DESCRIPTION
The foreach command implements a loop where the loop variable(s) take on values from one or more lists. In the simplest case there is one
loop variable, varname, and one list, list, that is a list of values to assign to varname. The body argument is a Tcl script. For each
element of list (in order from first to last), foreach assigns the contents of the element to varname as if the lindex command had been
used to extract the element, then calls the Tcl interpreter to execute body.
In the general case there can be more than one value list (e.g., list1 and list2), and each value list can be associated with a list of
loop variables (e.g., varlist1 and varlist2). During each iteration of the loop the variables of each varlist are assigned consecutive
values from the corresponding list. Values in each list are used in order from first to last, and each value is used exactly once. The
total number of loop iterations is large enough to use up all the values from all the value lists. If a value list does not contain enough
elements for each of its loop variables in each iteration, empty values are used for the missing elements.
The break and continue statements may be invoked inside body, with the same effect as in the for command. Foreach returns an empty string.
EXAMPLES
The following loop uses i and j as loop variables to iterate over pairs of elements of a single list. set x {} foreach {i j} {a b c d e f}
{
lappend x $j $i } # The value of x is "b a d c f e" # There are 3 iterations of the loop.
The next loop uses i and j to iterate over two lists in parallel. set x {} foreach i {a b c} j {d e f g} {
lappend x $i $j } # The value of x is "a d b e c f {} g" # There are 4 iterations of the loop.
The two forms are combined in the following example. set x {} foreach i {a b c} {j k} {d e f g} {
lappend x $i $j $k } # The value of x is "a d e b f g c {} {}" # There are 3 iterations of the loop.
SEE ALSO
for(n), while(n), break(n), continue(n)
KEYWORDS
foreach, iteration, list, looping
Tcl foreach(n)