I am new to scripting , I am trying to rebuild a script based on an old script. Can someone help me figure out what the script is doing? This is only a part of the script.
I am looking to interpret these two points in the scripts:-
1)
I do not understand when its doing test='echo $?', what is assigned in this step to test
I am looking to interpret these two points in the scripts:-
1)
I do not understand when its doing test='echo $?', what is assigned in this step to test
$? is a special variable, the return code of the last command. The return code is a number, zero for success, anything else for error.
...but they didn't need to use backticks `` (same key as ~) to get it into the variable test. Commands in backticks become strings, so you could do things like LINE=`grep username /etc/passwd` to read a matching line from a file into a variable.
What I figured out is it's sending stderr and stdout to the log file. Is that what its doing?
Depends what command is, of course. The redirections are sending all its output into the log file, yes.
What the script is doing, is running command over and over until it succeeds. When it fails, it must be returning 2, since that's what the loop checks for, and when it does, it keeps running it until it returns (in $?) something else.
Strongly advise that you do not name an Environment Variable with the same name as the unix command test .
The value of $? is the integer exit code of the most recent command executed in your Shell. Exit code zero means "non-failure" of the command itself. Other values should be documented for the program but can often be a matter of "test-and-detect".
Hello,
How come the following script adds each numeric value to a total sum ?
x=$1
func()
{
for i in $1 $2 $3; do
let x= $x+$i
done }
func "8 8 8" 9 9
echo $x
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hi hi how are are you
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Hi,
New to this forum, as well as to unix scripting..need help to understand below script ...
sendNotice_sp()
{
ATTACH=${LNXLOG:-}
if ; then
if ; then
mail -s "$ERR_MSG" $ERR_EMAIL_TO < $ATTACH
fi
else
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fi
}
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for file in *--*
do
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changes to
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sub findb{
my ($exp1,$col1,$exp2,$col2)= @_; # $exp = expression to find, $col - column to search in
my $cnt=0;
my ($val1,$val2);
my ($beg,$end);
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