03-18-2003
Works like a charm...thanks.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I have the necessity to use this command:
cat file1 | grep $A | grep $B
where sometime A and, or, B are not set.
For example:
I set A=@
never defined or set B
The above command send a cat error.
Any idea?
Thanks.
Giovanni (1 Reply)
Discussion started by: gio123bg
1 Replies
2. Shell Programming and Scripting
Hello
I want to check for NULL variable..
but this is not working..please help
thanks in advance
esham (2 Replies)
Discussion started by: esham
2 Replies
3. Shell Programming and Scripting
hi forum
i beginning with script and i want test un null variable in a schell
i just don t know the syntax here is a litle example
y=test
echo $y
unset y
echo $y (so here Y = Null)
if Y=Null
then
echo "y is null"
exit
fi (1 Reply)
Discussion started by: kykyboss
1 Replies
4. Shell Programming and Scripting
Hi,
I have to check whether an argument say $ARGV is not null in an if operator. Please let me know the operator. It would be great if you write a psuedo code.
Thanks in advance
Ammu (4 Replies)
Discussion started by: ammu
4 Replies
5. Shell Programming and Scripting
korn shell
If
then
update_smartcare_user_password "$u_id"
else
echo "Not a database user"
fi
i get this error
Syntax error at line *** : `then' is not expected.
what should i do.
I want to check whether $a is null or not. (2 Replies)
Discussion started by: sachin.gangadha
2 Replies
6. Shell Programming and Scripting
Hi all, I have a stupid question on NULL and zero(0).
In a script I've been working with, one of the lines is:
if &&
then
The problem I seem to have is when $Current_csm2 is null, this if block is not triggered, and I don't get why because I was under the impression that NULL!=0
Can... (7 Replies)
Discussion started by: spynappels
7 Replies
7. Shell Programming and Scripting
Hello, Unix-forums!
My problem:
read -p "Enter any number, please" number
sleep 1
echo $number | tr -d 0-9
test -z $number && echo "Thank you" || echo "This is not a number"Test always displays "This is not a number". It doesn't matter if I entered a or 1.
But if I order
echo... (2 Replies)
Discussion started by: intelinside
2 Replies
8. Shell Programming and Scripting
i have this code
for i in `cat sql_output.txt`
do
-- some script commands
done
sql_output.txt has 1 column with employee_ids
If the sql_output.txt is null then the do loop should not execute.
How can i implement this.
for i in `cat sql_output.txt`
If i is null or empty
then ... (5 Replies)
Discussion started by: rafa_fed2
5 Replies
9. Shell Programming and Scripting
Guys,
Please help me on the below
sample.cfg
var=NULL
sample.sh
#!/bin/sh
. /sample.cfg
if ;then
1 st command here
else
2 nd command here
fi (3 Replies)
Discussion started by: AraR87
3 Replies
10. Shell Programming and Scripting
DELETE=`cat $logfile1 | egrep -i "Delete" | sed 's/ */ /g' | cut -d" " -f2`
INSERT=`cat $logfile1 | egrep -i "Insert" | sed 's/ */ /g' | cut -d" " -f2`
UPDATE=`cat $logfile1 | egrep -i "Update" | sed 's/ */ /g' | cut -d" " -f2`
I need soming like below:
if value is null... (8 Replies)
Discussion started by: Veera_V
8 Replies
mt(1) General Commands Manual mt(1)
Name
mt - magnetic tape manipulating program
Syntax
mt [-f tapename] command [count]
Description
The command permits the operation of a magnetic tape drive.
Options
The -f flag option uses the specified tape device (next argument) in place of either that tape device defined by your TAPE environment
variable (.login or .profile) or /dev/nrmt0h.
Some operations may be performed multiple times by specifying count. By default, performs the requested operation once.
The command argument defines the operation to be performed. Only as many characters as are required to uniquely identify a command need be
specified.
The following is a list of commands:
bsf Backspace count files.
bsr Backspace count records.
cache Allows to use the cache buffer on a tape drive that has the cache buffer feature.
clhrdsf Clear hardware/software problem. Works with tape drives which use the TMSCP tape controller interface This command is
restricted to root access only.
clserex Clear serious exception. Works with tape drives which use the TMSCP tape controller interface
clsub Clear subsystem. Works with tape drives which use the TMSCP tape controller interface This command is restricted to
root access only.
eof, weof Write count end-of-file marks at the current position on the tape.
eotdis Disable end-of-tape detection. When the end of tape is reached, the tape will run off the reel. Only the superuser
can issue this command. The command remains in effect for the device until end-of-tape detection is enabled with the
eoten command.
eoten Enable end-of-tape detection. When the end-of-tape markers are reached, the tape is halted on the reel, between the
two end-of-tape markers. Only the superuser can issue this command. The command remains in effect for the device
until end-of-tape detection is disabled with the eotdis command. This is the default mode after a system boot.
fsf Forward-space count files.
fsr Forward-space count records.
nocache Disables the use of the cache buffer for any tape drive that has the cache buffer feature.
offline, rewoffl Rewind the tape and place the tape unit off-line.
retension Retensions the tape. Retension means moving the tape one complete pass between EOT and BOT.
rewind Rewind the tape.
status Print status information about the tape unit.
Examples
This example shows how to rewind the tape
mt -f /dev/rmt0l rewind
This example shows how to backspace the tape nmt1h three files:
mt -f /dev/nrmt1h bsf 3
This example shows how to write two end-of-file marks at the current position on tape nmt6h:
mt -f /dev/nrmt6h eof 2
Return Values
In shell scripts, returns a 0 exit status when the operation(s) were successful, 1 if the command was unrecognized, and 2 if an operation
failed.
Files
/dev/rmt?h or /dev/rmt?l
Raw magnetic tape interface with rewind when closed
/dev/nmt?h or /dev/nmt?l
Raw magnetic tape interface with no rewind when closed
See Also
dd(1), tar(1), ioctl(2), mtio(4), tms(4), environ(7)
mt(1)