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Full Discussion: Using variables created sequentially in a loop while still inside of the loop [bash]
Top Forums Shell Programming and Scripting Using variables created sequentially in a loop while still inside of the loop [bash] Post 302327901 by DeCoTwc on Monday 22nd of June 2009 11:54:58 PM
Old 06-23-2009
Using variables created sequentially in a loop while still inside of the loop [bash]
I'm trying to understand if it's possible to create a set of variables that are numbered based on another variable (using eval) in a loop, and then call on it before the loop ends.

As an example I've written a script called question (The fist command is to show what is the contents of the variable $tab)
Code:
    (23:32:12\[deco@S.Man)
    [~/bin]$ listQpsk 40|grep -w [1-4]
    40 SMANHUBAQPSK1          1    1344      1195        88
    40 SMANHUBAQPSK1          2    1668      1470        88
    40 SMANHUBAQPSK1          3    1881      1539        81
    40 SMANHUBAQPSK1          4    1686      1409        83


    (23:18:42\[deco@S.Man)
    [~/bin]$ cat question
    #!/usr/bin/bash
    tab=`listQpsk 40|grep -w [1-4]`
    seq=1
    num=4
    until [[ $seq -gt $num ]];do
    eval count$seq=`echo "$tab"|grep -w $seq|awk '{print $5}'`
    seq=$(($seq+1))
    done
    echo $count1
    echo $count2
    echo $count3
    echo $count4

When I run this I get
Code:
    (23:32:23\[deco@S.Man)
    [~/bin]$ ./question 
    1195
    1471
    1538
    1409

Which is exactly what I would expect, but is there a way to move the echo commands inside of the until loop so that part of the loop is echoing the value of the variable that was just created. Something like:

Code:
    until [[ $seq -gt $num ]];do
    eval count$seq=`echo "$tab"|grep -w $seq|awk '{print $5}'`
    seq=$(($seq+1))
    echo "$count$seq"
    done

 

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qb-blackbox

QB-BLACKBOX(8)						      System Manager's Manual						    QB-BLACKBOX(8)

NAME

       qb-blackbox - Display "flight data" from the "blackbox".

SYNOPSIS

       qb-blackbox <blackbox files>...

DESCRIPTION

       qb-blackbox Print out the logs (including debug logs) that were recorded using libqb's blackbox.

EXAMPLES

       Get info to help developers diagnose a crash.
	      $ qb-blackbox /var/lib/corosync/fdata
	      Dumping the contents of /var/lib/corosync/fdata
	      Mar 23 20:58:57 message_handler_orf_token():3677 install seq 0 aru 0 high seq received 0
	      Mar 23 20:58:57 message_handler_orf_token():3696 retrans flag count 4 token aru 0 install seq 0 aru 0 0
	      Mar 23 20:58:57 old_ring_state_reset():1487 Resetting old ring state
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	      Mar 23 20:58:57 memb_state_operational_enter():1779 Delivering to app 1 to 0
	      Mar 23 20:58:57 sync_abort():594 ENTERING sync_abort()
	      Mar 23 20:58:57 sync_save_transitional():586 ENTERING sync_save_transitional()
	      Mar 23 20:58:57 member_object_joined():301 Member joined: r(0) ip(192.168.122.1)
	      Mar 23 20:58:57 sync_abort():594 ENTERING sync_abort()

SEE ALSO

       qblog.h(3),

AUTHOR

       Angus Salkeld

								    2012-05-28							    QB-BLACKBOX(8)
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