I have a variable which should be any number between 1 and 50.
It could also be any string/empty string.
I have a code written below. The point is when the variable contains string.
I don't want the code below to error out. Instead fall in the else bucket.
How can I test a variable to see if its in the right format?
The format for the variable would be 'DDMMYYYY HH:MM:SS' and is passed from a command line argument.
Any help would be appreciated (2 Replies)
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)
I'm using the following line in bash to test whether an argument supplied is an absolute path or not:
if echo $1 | grep '^/' > /dev/null
then
absolute=1
else
absoute=0
fi
The line appears to work but seems somewhat unprofessional looking to me. Is it an acceptable... (2 Replies)
hi,
i store a constant in a variable and want to test whether it is M or Z.
how can i achieve this?? please help
variable='M'
if
then
ehco 'success'
fi;
is this right ?? (2 Replies)
I'm trying to test and see whether a variable that is being extracted from a line in a file is numeric or not. I have tried everything that I can think of and I cannot figure out how to get it to work. I am trying to test and see if the string extracted contains 5 numeric digits. This is what I... (8 Replies)
This is the code:
while test 1 -eq 1
do
read a
$a
if test $a = stop
then
break
fi
done
I read a command on every loop an execute it.
I check if the string equals the word stop to end the loop,but it say that I gave too many arguments to test.
For example echo hello.
Now the... (1 Reply)
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)
Hi,
I am trying to get the oracle variables and pass the values in sql placed in procedure.
VARIABLE
vstat='ASDS,FGDS,VCGD,VCXC'
Query :
select distinct dept from College
where section in ('C','D')
AND CODES =''
AND NAMES IN ('RAJ','SAM');
I want CODES values to be taken from vstat... (1 Reply)
Hello,
I have two files, f1 and f2. f1 has 5 columns like so:
a b c d 154
e f g h 365
.....
f2 has two columns, the first column contains the name of the above file and second column contains a constant which is to be used for division.
e.g.
file1 56
I want to divide the 5th... (2 Replies)
Discussion started by: Gussifinknottle
2 Replies
LEARN ABOUT OPENDARWIN
for
for(n) Tcl Built-In Commands for(n)
__________________________________________________________________________________________________________________________________________________NAME
for - ``For'' loop
SYNOPSIS
for start test next body
_________________________________________________________________DESCRIPTION
For is a looping command, similar in structure to the C for statement. The start, next, and body arguments must be Tcl command strings,
and test is an expression string. The for command first invokes the Tcl interpreter to execute start. Then it repeatedly evaluates test
as an expression; if the result is non-zero it invokes the Tcl interpreter on body, then invokes the Tcl interpreter on next, then repeats
the loop. The command terminates when test evaluates to 0. If a continue command is invoked within body then any remaining commands in
the current execution of body are skipped; processing continues by invoking the Tcl interpreter on next, then evaluating test, and so on.
If a break command is invoked within body or next, then the for command will return immediately. The operation of break and continue are
similar to the corresponding statements in C. For returns an empty string.
Note: test should almost always be enclosed in braces. If not, variable substitutions will be made before the for command starts execut-
ing, which means that variable changes made by the loop body will not be considered in the expression. This is likely to result in an
infinite loop. If test is enclosed in braces, variable substitutions are delayed until the expression is evaluated (before each loop iter-
ation), so changes in the variables will be visible. For an example, try the following script with and without the braces around $x<10:
for {set x 0} {$x<10} {incr x} {
puts "x is $x"
}
SEE ALSO
break, continue, foreach, while
KEYWORDS
for, iteration, looping
Tcl for(n)