I guess as they say, RTFM more carefully. Just kidding.
NAME=${0##*/}
simply gets the name of the currently executing script. The $0 is what does it, and the rest strips of the leading path names. It's useful when the script name is supposed to different things depending on how its invoked. For instance, if you have a softlink to your script named "foo" and another softlink named "bar", then your script can do print out "FU" instead of "Beyond All Recognition". Or something.
set -xv +xv are shorthand for
Code:
set -x
set -v
The first turns on "eXecution debugging". Every command that is executed, and after parsing, is printed to stderr. The second turns on "Verbose mode" which prints to stderr every line that is read in and before being parsed, whether or not it is executed.
Found this piece of code written in ksh. I have no ideas what do the stuff like ${SRF##*\.} do.
SUFFIX=${SRF##*\.}
if ; then
SUFFIX=""
fi
I have encountered similar expressions in other programs also. Any pointers on where to learn more about these... (1 Reply)
Discussion started by: jyotipg
1 Replies
2. Post Here to Contact Site Administrators and Moderators
woofie,
Your posts are being deleted because your use of profanity.
I am close to changing your status to read only.
In fact, if you argue with the mods again, I will ban you from these boards.
Neo (1 Reply)
Looking at the member list, there are alot of interesting names, some unique, some bizarre, and some that are just plain. How did you come by your name? Why did you choose your label?
Me? Well, I wish I could change mine. I chose Google because thats how I stumbled upon this site. I wasn't sure... (66 Replies)
#! /bin/bash
head -5 $1
echo "remove $1 ?"
read answer
if
then
echo invalid answer
elif
rm $1
echo "$1 is deleted"
elif
then
echo file is not deleted
else
echo "invalid answer"
fi
What i really want this to do is to ask to delete the file or not..it says something wrong... (1 Reply)
#! /bin/bash
USAGE=" | ]
if
then
echo "$USAGE"
exit 1
fi
while getopts lb: OPTION
do
case $(OPTION)in
a) echo Hi there!
exit 2;;
b) echo hello
o) OARG=$OPTARG;;
\?)echo "$USAGE" ;;
exit 2;;
esac
done
shift `expr... (1 Reply)
can anyone tell me why this code doesn't work how its supposed to, its the hangman game but it doesn't play how its supposed to
#!/bin/bash
NoAttempts="0"
livesgiven="5"
LivesRemain=$livesgiven
LettersAttempted=""
wordfile=words
numwords=0
function menu()
{
clear
cat << menu... (1 Reply)
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
ls -ld htdocs
drwxr-x--- 3 root root 8192 2006-11-19 10:41 htdocs
How would a host administrator... (1 Reply)
Discussion started by: Larry_1
1 Replies
LEARN ABOUT REDHAT
after
after(n) Tcl Built-In Commands after(n)
__________________________________________________________________________________________________________________________________________________NAME
after - Execute a command after a time delay
SYNOPSIS
after ms
after ms ?script script script ...?
after cancel id
after cancel script script script ...
after idle ?script script script ...?
after info ?id?
_________________________________________________________________DESCRIPTION
This command is used to delay execution of the program or to execute a command in background sometime in the future. It has several forms,
depending on the first argument to the command:
after ms
Ms must be an integer giving a time in milliseconds. The command sleeps for ms milliseconds and then returns. While the command is
sleeping the application does not respond to events.
after ms ?script script script ...?
In this form the command returns immediately, but it arranges for a Tcl command to be executed ms milliseconds later as an event
handler. The command will be executed exactly once, at the given time. The delayed command is formed by concatenating all the
script arguments in the same fashion as the concat command. The command will be executed at global level (outside the context of
any Tcl procedure). If an error occurs while executing the delayed command then the bgerror mechanism is used to report the error.
The after command returns an identifier that can be used to cancel the delayed command using after cancel.
after cancel id
Cancels the execution of a delayed command that was previously scheduled. Id indicates which command should be canceled; it must
have been the return value from a previous after command. If the command given by id has already been executed then the after can-
cel command has no effect.
after cancel script script ...
This command also cancels the execution of a delayed command. The script arguments are concatenated together with space separators
(just as in the concat command). If there is a pending command that matches the string, it is cancelled and will never be executed;
if no such command is currently pending then the after cancel command has no effect.
after idle script ?script script ...?
Concatenates the script arguments together with space separators (just as in the concat command), and arranges for the resulting
script to be evaluated later as an idle callback. The script will be run exactly once, the next time the event loop is entered and
there are no events to process. The command returns an identifier that can be used to cancel the delayed command using after can-
cel. If an error occurs while executing the script then the bgerror mechanism is used to report the error.
after info ?id?
This command returns information about existing event handlers. If no id argument is supplied, the command returns a list of the
identifiers for all existing event handlers created by the after command for this interpreter. If id is supplied, it specifies an
existing handler; id must have been the return value from some previous call to after and it must not have triggered yet or been
cancelled. In this case the command returns a list with two elements. The first element of the list is the script associated with
id, and the second element is either idle or timer to indicate what kind of event handler it is.
The after ms and after idle forms of the command assume that the application is event driven: the delayed commands will not be executed
unless the application enters the event loop. In applications that are not normally event-driven, such as tclsh, the event loop can be
entered with the vwait and update commands.
SEE ALSO
bgerror(n), concat(n), update(n), vwait(n)
KEYWORDS
cancel, delay, idle callback, sleep, time
Tcl 7.5 after(n)
09-30-2008
