Another question, is it possible to, in a for-loop incrementing until it reaches a certain number, to have it loop again without incrementing? Just have it drop what it is doing when it reaches this command and start again at the same number it was at? I know I could make a while loop and just... (0 Replies)
Hi All,
I amlearning UNIX scripting. I have a small query. I would be thankful if any one helps me out.
I have a below piece of code which delets the files. If file dosent have the permissions to delete a particular file I have used 2>>operator to track the error code.
But my objective is... (1 Reply)
I wonder how to stop further loop iterations when conditions gets false e.g.
This file.txt contains the following structure :
1
2
3
4
5
6
7
8
9
10
How to stop iteration when if statement gets false ?
for n in `cat file.txt`
do
if (( n<=5 )) (1 Reply)
question :how can i iterate to next item in for loop with the loop
e.g
for i in `cat abc.txt`
do
echo $i // this will display first line
i=$i+1; // this doesnt work for me.
echo $i; //this will display secound line
done
question: is my approach to manipulate text good?
I have... (3 Replies)
I have written the following script to update some Debian boxes.
#!/bin/bash
mxg_hosts_file="/etc/mxg/ssh-hosts"
while read line ; do
mxg_host="$(echo ${line} | awk -F":" '{print $1}')"
mxg_port="$(echo ${line} | awk -F":" '{print $2}')"
echo "Connecting and Upgrading... (3 Replies)
for VGLIST in `lsvg -o`
do
CLOSED_OUT=`echo $VGLIST | lsvg -l $VGLIST | awk '{print $6 " " $7}' | grep closed`
if ]; then
echo "Filesystems $CLOSED_OUT in VG that are in Closed status"
else
echo "\n Some message"
fi
Above Code is working fine, but echo "Filesystems $CLOSED_OUT... (8 Replies)
I have a script with logic like:
my_function()
{
if
mkdir $1
mkdir mydir_${2}
else
do something else
fi
}
read in list of items
while read list
do
my_function $list `date`
done
so basically it will make a directory for every name in the list and create a directory with the... (6 Replies)
bash in RHEL 6.4
I have a requirement in which I want to get the iteration count from a WHILE LOOP.
The below mentioned simple script test.sh works fine. In the below script, the WHILE loop will iterate every 5 seconds infinitely until it greps the string BASKETBALL from /tmp/somestring.txt... (6 Replies)
I am trying to check multiple server's "uptime" in a loop over "ssh".
When I execute multiple ssh commands with hard coded servernames script is executing fine.
But when I pass server names using while loop, script is exiting after checking first server's status, why?
# serverList... (8 Replies)
Hello,
I've written a script to automate encoding of all the MP4 files in a directory (incl. subdirectories). But unfortunately it's running for the first MP4 file only.
My machine details:
root@Ubuntu16:~# uname -a
Linux Ubuntu16 4.10.0-28-generic #32~16.04.2-Ubuntu SMP Thu Jul 20 10:19:48... (2 Replies)
Discussion started by: prvnrk
2 Replies
LEARN ABOUT OSX
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
This loop prints every value in a list together with the square and cube of the value:
set values {1 3 5 7 2 4 6 8} ;# Odd numbers first, for fun!
puts "Value Square Cube" ;# Neat-looking header
foreach x $values { ;# Now loop and print...
puts " $x [expr {$x**2}] [expr {$x**3}]"
}
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)