05-30-2008
! operator in variable
Can any body kindly tell me the purpose of ! operator in the following expression:
y=${!x}
Actually when i execute this statement on my solaris 10 terminal, i get empty output.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I am trying to check two variables and if both are blank I want to set a flag:
the_f3_pid=`rsh $target ps -ef | grep "f3.eab" | awk '{print $2}'`
the_f7_pid=`rsh $target ps -ef | grep "f7.eab" | awk '{print $2}'`
if ; then
y=1
fi
I get an error:
./script_name: test: 0403-021 ]... (4 Replies)
Discussion started by: rcarnesiii
4 Replies
2. HP-UX
hi,
i was trying to club to test condition with if.
if -o ; then
it is giving me error message, i wanted to ask how can we check two condtions with one if. (1 Reply)
Discussion started by: babom
1 Replies
3. Shell Programming and Scripting
When reading over some perl code in a software document, I came across an assignment statement like this
$PATH = ${PROJECT}/......./....
In this particular form of scalar variable assignment, what does the curly braces operators do ? Also, what is the benefit in doing scalar assignment this... (3 Replies)
Discussion started by: JamesGoh
3 Replies
4. Shell Programming and Scripting
Hi,
I'm new to UNIX, at least shell programming and am having trouble figuring out a problem i'm having. In one section in my nested if statement, i want the program to test if the file does not exist, based on an argument supplied at the command line by the user. What i have is
elif ; then... (3 Replies)
Discussion started by: rowlf
3 Replies
5. Shell Programming and Scripting
I have a string of commands I am piping some data through and I want to allow command line switches to select which commands are used. I want to do something like this: OPTION="| command3"
command1 -a -b c.txt | command2 -d -e $OPTION >result.txt
I want to do it that way because OPTION may be... (1 Reply)
Discussion started by: KenJackson
1 Replies
6. UNIX for Dummies Questions & Answers
All,
THe below is my script , when i use this i am getting nothing . could any one help me to know what is the use of the << operator below
su - $8 << supo
echo "exportsph $2 $1 $3 $4"
exportsph $2 $1 $3 $4
supo
i also tried as individual command su - userid << supo , when i do... (3 Replies)
Discussion started by: arunkumar_mca
3 Replies
7. Shell Programming and Scripting
Hey ,
I'm trying to perform the following command, however it cannot read the variable assigned earlier. I'm not sure why this happen. Please help thanks
while :
do
echo "what's ur name? (if none just press )"
read name
changeName = echo $name | sed "s/on/ey/"
echo $changeName #this... (8 Replies)
Discussion started by: sexyTrojan
8 Replies
8. UNIX for Dummies Questions & Answers
im new to bash scripting and im just using online tutorials and trial and error. i wanted to write a script to read numbers from a file and find their sum:
#!/bin/bash
theSum=0
for line in $(cat numbers.txt)
do
let "theSum = theSum + $line"
echo "$line"
done
echo "The sum is... (3 Replies)
Discussion started by: astrolux444
3 Replies
9. Shell Programming and Scripting
I wanted to write a bash script which take a variable X with math operator as (* or / or + or - or % and more ....). Instead of writing logic for each condition can we have a generic logic. Like sudo code below.
A=10, B=20
P = $A $X $B;
echo $P;
-------------
when X has value "*" echo $P,... (1 Reply)
Discussion started by: samcompda
1 Replies
10. Shell Programming and Scripting
I have a little code block (executing on AIX 7.1) that I cannot understand why the NOTFREE=0 does not appear to be assigned even though it goes through that block. This causes a unary operator issue.
#!/bin/bash
PLATFORM="AIX"
NEEDSPC=3000
set -x
if ; then
lsvg | grep -v rootvg | while... (6 Replies)
Discussion started by: port43
6 Replies
LEARN ABOUT CENTOS
execute
EXECUTE(7) PostgreSQL 9.2.7 Documentation EXECUTE(7)
NAME
EXECUTE - execute a prepared statement
SYNOPSIS
EXECUTE name [ ( parameter [, ...] ) ]
DESCRIPTION
EXECUTE is used to execute a previously prepared statement. Since prepared statements only exist for the duration of a session, the
prepared statement must have been created by a PREPARE statement executed earlier in the current session.
If the PREPARE statement that created the statement specified some parameters, a compatible set of parameters must be passed to the EXECUTE
statement, or else an error is raised. Note that (unlike functions) prepared statements are not overloaded based on the type or number of
their parameters; the name of a prepared statement must be unique within a database session.
For more information on the creation and usage of prepared statements, see PREPARE(7).
PARAMETERS
name
The name of the prepared statement to execute.
parameter
The actual value of a parameter to the prepared statement. This must be an expression yielding a value that is compatible with the data
type of this parameter, as was determined when the prepared statement was created.
OUTPUTS
The command tag returned by EXECUTE is that of the prepared statement, and not EXECUTE.
EXAMPLES
Examples are given in the EXAMPLES section of the PREPARE(7) documentation.
COMPATIBILITY
The SQL standard includes an EXECUTE statement, but it is only for use in embedded SQL. This version of the EXECUTE statement also uses a
somewhat different syntax.
SEE ALSO
DEALLOCATE(7), PREPARE(7)
PostgreSQL 9.2.7 2014-02-17 EXECUTE(7)