I've got this problem, if I modify an array in the loop and print it, everything is fine as long as I stay in the loop. But, when I print it outside the loop, nothing happens... How can I solve this problem?
Here I prepared a sample for you to see my problem;
Code:
zgrw@Rain:~$ cat test
asd
123
13
1234
Code:
zgrw@Rain:~$ cat test.sh
#!/bin/bash
declare -a asd
c=0
cat test | while read line; do
asd[$c]=$line
echo ${asd[@]}
((c++))
done
echo "I wish you here"
echo ${asd[@]}
Output is;
Code:
zgrw@Rain:~$ ./test.sh
asd
asd 123
asd 123 13
asd 123 13 1234
I wish you here
zgrw@Rain:~$
I am just stucked in syntax.This is more like a array and for loop problem.
I want to use ls -l command and get filezise and filename of all filenames in the directory in an array (say array#1).
After 2 minutes of sleep, i want to get the same information in another array (say array#2).
The... (4 Replies)
Hello,
I have a problem with my script whereby it does not want to loop.
The function of my script is to FTP into a server and go to each directory/volume in the array 'VOL'. The way the loop is suppose to work, is to go into the first volume, get the files of R(yesterday's date) and... (3 Replies)
Hi everyone:)
I have 2 files - IN & OUT. Example:
IN
A:13:30
B:45:40
.
.
. UNLIMITED
OUT
Z:12:24
Y:20:15
.
.
. UNLIMITED
I want first row of numbers of IN - OUT. Example 13-12 45-20
My code is (2 Replies)
So I'm trying to read datafile into an array, with each line representing one variable in the array. I'm successful at first but somehow it keeps getting erased.
i=0
grep '.*' datafile | while read line
do
echo $i
array=$(echo $line)
echo ${array} #printing array to make sure it's... (5 Replies)
Hi All,
I am trying to run a do while for an array. And in the do while, I'm trying to get a user response. Depending on the the answer, I go ahead and do something or I move on to next element in the array.
So far I can read the array, but I can't get the if statement to work. Any suggestions... (5 Replies)
Below is a test script I was trying to use so that I could understand why the logic was not working in a larger script. While accessing and printing array data inside the while loop, everything is fine. Outside the loop, i guess everything is null?? The for loop that is meant to cycle... (4 Replies)
Hello All,
Maybe I'm Missing something here but I have NOOO idea what the heck is going on with this....?
I have a Variable that contains a PATTERN of what I'm considering "Illegal Characters". So what I'm doing is looping
through a string containing some of these "Illegal Characters". Now... (5 Replies)
Hi, I have the following problem that is beyond what I can currently do with bash scripting.
In file 1, I have ~ 2500000 values. Note this file is not sorted.
3 19 LABEL_A
3 37 LABEL_B
2 12 LABEL_C
1 15 LABEL_D
I have a list of values in "file 2" ~ 25000 unique lines:
Note -... (6 Replies)
Hi there,
A bit new to bash and am having an issue with a for loop. I look for filenames in a specified directory and pull the date string from each meeting a certain criteria, and then would like to make a directory for each date found, like this:
search 20180101.gz 20180102.gz 20180103.gz... (5 Replies)
Discussion started by: mwheeler12
5 Replies
LEARN ABOUT CENTOS
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)