This question is a sequel of sorts to my earlier question. The users on this site kindly helped me determine how to write a bash for loop that iterates over string values. For example, suppose that a loop control variable fname iterates over the strings "a.txt" "b.txt" "c.txt". I would like to echo "yes!" when fname has the value "a.txt" or "c.txt", and echo "no!" otherwise.
I have the following bash script:
#!/bin/bash
upperlim=10
for i in {0..10}
do
echo $i
done
for i in {0..$upperlim}
do
echo $i
done
The first for loop (without the variable upperlim in the loop control) works fine, but the second for loop (with the variable upperlim in the loop control) does not. Is there any way that I can modify the second for loop so that it works? Thanks for your time.
I set the a array as an environment variable in this manner
eg.
Ok so I got a little bored and desided to make a fun little bash script that you can use to scare Linux neewbies :)
Here is the code:
Quote:
#!/bin/bash
clear
echo "Formating disk(s): " /dev/sd*
sleep 2
echo "Initialising..."
sleep 2
echo "Are you sure you want to format these disks?"
# Declare variable choice and assign value
going through advanced bash scripting guide example 3.3 running a loop in background, i found this :
#!/bin/bash
# background-loop.sh
for i in 1 2 3 4 5 6 7 8 9 10 # First loop.
do
echo -n "$i "
done & # Run this loop in background.
# Will sometimes execute after second loop.
echo # This 'echo' sometimes will not display.
for i in 11 12 13 14 15 16 17 18 19 20 # Second loop.
do
echo -n "$i "
when I run from bash shell the command:
bash
for i in 1 2 3 ; do echo $i ; done
1
2
3
but when I switch to tcsh and want to run:
tcsh
bash -c for i in 1 2 3 ; do echo $i ; done
i: -c: line 1: syntax error near unexpected token `newline'
i: -c: line 1: `for'
i: Undefined variable.
please advice why I get errors ( I run the for loop from bash -c its the same ?
and what I ne
Hi
As bash does not support multidimensional arrays (?), I need some help with a problem.
is this possible?
its kind of like incrementing the value of a number in a variable. but in this case, instead of the value of the variable being a number, it's just contents/strings/characters/alpha-numeric etc.
A For loop is, as its name says a loop that executes certain code or commands for a given number of datum.
From Wikipedia:
for loop is a programming language statement which allows code to be repeatedly executed. A for loop is classified as an iteration statement.
For Loop Syntax
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