read -p command (input) inside the while loop - while-loop

I am trying to read multiple inputs from user using while loop.
I tried below
while
do
read -p "Enter Server Names : " multi_act
done
'read -p' command is not working inside the while loop, How can I solve this?

I got it fixed as below
exec 5< file1
while read <&5 a; do
echo before
read var
echo after
done
exec 5<&-
its working like a charm.

Related

How to store a command output in OpenVMS

Im having an issue writing a DCL in OpenVMS in that I need the DCL to call a command and capture its output (but not output the output to the screen) Later on in the DCL I then need to print that output I stored.
Heres an example:
ICE SET FASTER !This command sets my environment to the "Faster" environment.
The above command outputs this if executed directly in OpenVMS:
Initialising TEST Environment to FASTER
--------------------------------------------------------------------------------
Using Test Search rules FASTER
Using Test Search rules FASTER
--------------------------------------------------------------------------------
dcl>
So I created a DCL in an attempt to wrap this output in order to display a more simplified output. Heres my code so far:
!************************************************************************
$ !* Wrapper for setting ICE account. Outputs Environment
$ !************************************************************************
$ on error then goto ABORT_PROCESS
$ICE_DCL_MAIN:
$ ice set 'P1'
$ ICE SHOW
$ EXIT
$ABORT_PROCESS:
$ say "Error ICING to: " + P1
$ EXIT 2
[End of file]
In the lines above ICE SET 'P1' is setting the ice environment, but I dont want this output to be echoed to VMS. But what I do want is to write the output of $ICE SHOW into a variable and then echo that out later on in the DCL (most of which ive omitted for simplification purposes)
So what should be outputted should be:
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
Instead of:
Initialising TEST Environment to FASTER
--------------------------------------------------------------------------------
Using Test Search rules FASTER
Using Test Search rules FASTER
--------------------------------------------------------------------------------
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
Ive had a look through the manual and im getting a bit confused so I figured I tried here. Id appreciate any pointers. Thanks.
EDIT
Here is what ive come up with after the comments, the problem im having is when I connect to VMS using an emulator such as SecureCRT the correct output is echoed. But when I run the DCL via my SSH2 library in .NET it doesnt output anything. I guess thats because it closes the SYS$OUTPUT stream temporarily or something?
$ !************************************************************************
$ !* Wrapper for setting ICE account. Outputs Environment
$ !************************************************************************
$ on error then goto ABORT_PROCESS
$ICE_DCL_MAIN:
$ DEFINE SYS$OUTPUT NL:
$ ice set 'P1'
$ DEASSIGN SYS$OUTPUT
$ ice show
$ EXIT
$ABORT_PROCESS:
$ say "Error ICING to: " + P1
$ EXIT 2
[End of file]
EDIT 2
So I guess really I need to clarify what im trying to do here. Blocking the output doesnt so matter so much, im merely trying to capture it into a Symbol for example.
So in C# for example you can have a method that returns a string. So you'd have string myResult = vms.ICETo("FASTER"); and it would return that and store it in the variable.
I guess im looking for a similar thing in VMS so that once ive iced to the environment I can call:
$ environment == $ICE SHOW
But I of course get errors with that statement
The command $ assign/user_mode Thing Sys$Output will cause output to be redirected to Thing until you $ deassign/user_mode Sys$Output or next executable image exits. An assignment without the /USER_MODE qualifier will persist until deassigned.
Thing can be a logical name, a file specification (LOG.TXT) or the null device (NLA0:) if you simply want to flush the output.
When a command procedure is executed the output can be redirected using an /OUTPUT qualifier, e.g. $ #FOO/output=LOG.TXT.
And then there is piping ... .
You can redirect the output to a temp file and then print its content later:
$ pipe write sys$output "hi" > tmp.tmp
$ ty tmp.tmp
VMS is not Unix, DCL is not Bash: you can not easily set a DCL symbol from the output of a command.
Your ICE SHOW prints one line, correct? The first word is always "current", correct?
So you can create a hack.
First let me fake your ICE command:
$ create ice.com
$ write sys$output "current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]"
^Z
$
and I define a dcl$path pointing to the directory where this command procedure is
so that I can use/fake the command ICE
$ define dcl$path sys$disk[]
$ ice show
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
$
Now what you need, create a command procedure which sets a job logical
$ cre deflog.com
$ def/job/nolog mylog "current''p1'"
^Z
$
And I define a command "current" to run that command procedure:
$ current="#deflog """
Yes, you need three of the double quotes at the end of the line!
And finally:
$ pipe (ice show | #sys$pipe) && mysym="''f$log("mylog")'"
$ sh symb mysym
MYSYM = "current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]"
$
On the other hand, I don't know what you are referring to C# and Java. Can you elaborate on that and tell us what runs where?
You can try using: DEFINE /USER SYS$OUTPUT NL:.
It works only for the next command and you dont need to deassign.
Sharing some of my experience here. I used below methods to redirect outputs to files.
Define/Assign the user output and then execute the required command/script afterwards. Output will be written to .
$define /user sys$output <file_path>
execute your command/script
OR
assign /user <file_path> sys$output
execute your command/script
deassign sys$output
To re-direct in to null device like in Unix (mentioned in above answers), you can use 'nl:' instead of
define /user sys$output nl:
or
assign /user nl: sys$output

connect to sqlplus only once without writing to a file in a loop

I have a requirement for which I need to write a ksh script that reads command line parameters into arrays and creates DML statements to insert records into an oracle database. I've created a script as below to achieve this. However, the user invoking the script doesn't have permission to write into the directory where the script has to run. So, is there a way we can fire multiple inserts on the database without connecting to sqlplus multiple times within the loop and at the same time, NOT create temp sql file as below? Any ideas are highly appreciated. Thanks in advance!
i=0
while (( i<$src_tbl_cnt ))
do
echo "insert into temp_table values ('${src_tbl_arr[$i]}', ${ins_row_arr[$i]}, ${rej_row_arr[$i]});" >> temp_scrpt.sql
(( i+=1 ))
done
echo "commit; disc; quit" >> temp_scrpt.sql
sqlplus user/pass#db # temp_scrpt.sql
Just use the /tmp directory.
The /tmp directory is guaranteed to be present on any unix-family server. It is there precisely for needs like this. Definitely do something like add the current process ID in the file name so that multiple users don't step on each other. So the total name is something like /tmp/temp_$PID_scrpt.sql or the like.
When done, be sure to also delete that file--say, in a line right after the sqlplus call. Thus be sure to store the file name in a variable and delete what's in that variable.
It should go without saying, but in a well run shop: 1) The admins should have put more than enough space in /tmp, 2) All the users in the community should not be deleting other's files in /tmp or overloading it so it runs out of space. 3) The admins should setup a job that deletes files from /tmp after a certain age so that if your script fails before it deletes the temporary file, it won't be there forever.
So really, this answer is more about /tmp and managing it effectively--but that really is what you need. Using temporary files is a powerful technique, so your design is good. And the reality that users often won't have rights in a directory is common, so /tmp is your answer.
Instead of creating a temporary file you can directly pipe the output of an input generating block into sqlplus, in your shell script.
Example:
{
echo 'set auto off;'
for ((i=0; i<100; i++)); do
echo "insert into itest(i) values ($i);"
done
# echo 'rollback;' # for testing
echo 'commit;'
} | sqlplus -S juser/secret#db > /dev/null
This works with Ksh 93 and Bash (perhaps even with Ksh 88 modulo the (( expression syntax).
The corresponding DDL statement for the test table:
create table itest ( i number(36) ) ;
PS: Btw, even when creating a temporary file is preferred - redirecting the output is way more efficient than doing an append-style redirect for each line, e.g.:
{ for ((i=0; i<100; i++)); do echo "line $i"; done; echo end; } > foo.tmp
the below piece of code will keep connecting to SQLplus multiple times or it will connect only once ?
{
echo 'set auto off;'
for ((i=0; i<100; i++)); do
echo "insert into itest(i) values ($i);"
done
echo 'rollback;' # for testing
echo 'commit;'
} | sqlplus -S juser/secret#db > /dev/null

Error executing shell command in pig script

I have a pig script where in the beginning I would like to generate a string of the dates of the past 7 days from a certain date (later used to retrieve log files for those days).
I attempt to do this with this line:
%declare CMD7 input= ; for i in {1..6}; do d=$(date -d "$DATE -i days" "+%Y-%m-%d"); input="\$input\$d,"; done; echo \$input
I get an error :
" ERROR 2999: Unexpected internal error. Error executing shell command: input= ; for i in {1..6}; do d=$(date -d "2012-07-10 -i days" "+%Y-%m-%d"); input="$input$d,"; done;. Command exit with exit code of 127"
however the shell command runs perfectly fine outside of pig. I am really not sure what is going wrong here.
Thank you!
I have got a working solution but not as streamlined as you want, essentially I don't manage to get Pig to execute a complex shell statement in the declare.
I first wrote a shell script (let's call it 6-days-back-from.sh):
#!/bin/bash
DATE=$1
for i in {1..6}; do d=$( date -d "$DATE -$i days" +%F ) ; echo -n "$d "; done
Then a pig script as follow (let's call it days.pig):
%declare my_date `./6-days-back-from.sh $DATE`
A = LOAD 'dual' USING PigStorage();
B = FOREACH A GENERATE '$my_date';
DUMP B
note that dual is a directory containing a text file with a single line of text, for the purpose of displaying our variable
I called the script as follow:
pig -x local -param DATE="2012-08-03" days.pig
and got the following output:
({(2012-08-02),(2012-08-01),(2012-07-31),(2012-07-30),(2012-07-29),(2012-07-28)})

Expect script does not work under crontab

I have an expect script which I need to run every 3 mins on my management node to collect tx/rx values for each port attached to DCX Brocade SAN Switch using the command #portperfshow#
Each time I try to use crontab to execute the script every 3 mins, the script does not work!
My expect script starts with #!/usr/bin/expect -f and I am calling the script using the following syntax under cron:
3 * * * * /usr/bin/expect -f /root/portsperfDCX1/collect-all.exp sanswitchhostname
However, when I execute the script (not under cron) it works as expected:
root# ./collect-all.exp sanswitchhostname
works just fine.
Please Please can someone help! Thanks.
The script collect-all.exp is:
#!/usr/bin/expect -f
#Time and Date
set day [timestamp -format %d%m%y]
set time [timestamp -format %H%M]
#logging
set LogDir1 "/FPerf/PortsLogs"
et timeout 5
set ipaddr [lrange $argv 0 0]
set passw "XXXXXXX"
if { $ipaddr == "" } {
puts "Usage: <script.exp> <ip address>\n"
exit 1
}
spawn ssh admin#$ipaddr
expect -re "password"
send "$passw\r"
expect -re "admin"
log_file "$LogDir1/$day-portsperfshow-$time"
send "portperfshow -tx -rx -t 10\r"
expect timeout "\n"
send \003
log_file
send -- "exit\r"
close
I had the same issue, except that my script was ending with
interact
Finally I got it working by replacing it with these two lines:
expect eof
exit
Changing interact to expect eof worked for me!
Needed to remove the exit part, because I had more statements in the bash script after the expect line (calling expect inside a bash script).
There are two key differences between a program that is run normally from a shell and a program that is run from cron:
Cron does not populate (many) environment variables. Notably absent are TERM, SHELL and HOME, but that's just a small proportion of the long list that will be not defined.
Cron does not set up a current terminal, so /dev/tty doesn't resolve to anything. (Note, programs spawned by Expect will have a current terminal.)
With high probability, any difficulties will come from these, especially the first. To fix, you need to save all your environment variables in an interactive session and use these in your expect script to repopulate the environment. The easiest way is to use this little expect script:
unset -nocomplain ::env(SSH_AUTH_SOCK) ;# This one is session-bound anyway
puts [list array set ::env [array get ::env]]
That will write out a single very long line which you want to put near the top of your script (or at least before the first spawn). Then see if that works.
Jobs run by cron are not considered login shells, and thus don't source your .bashrc, .bash_profile, etc.
If you want that behavior, you need to add it explicitly to the crontab entry like so:
$ crontab -l
0 13 * * * bash -c '. .bash_profile; etc ...'
$

Parse sqlite query line by line

i have a problem which i cant figure out myself, i have a SQLite database which contains data
to retrieve the data i use a bash script and the command sqlite3 db "SELECT prkey FROM printers"
the output is something like this:
1
3
4
5
6
7
i need to parse each line and use it for my next command. and with out the use of a > file
regards Marco
The for loops work, but they are not very robust: they break if a line in the output has a space, and the shell must store the whole output of the query in memory before it starts running the loop. These two issues are easily dealt with:
sqlite3 db "SELECT ..." | while read prkey; do
echo "do stuff with $prkey"
done
#!/bin/bash
for line in $(sqlite3 db "SELECT prkey FROM printers"); do
echo "line is --> $line" # do stuff with $line
done
You can use for loop on the return value of the sqlite command.
for prkey in `sqlite3 db "SELECT prkey FROM printers"`; do
echo $prkey; #replace with your command
done;