I would like to have a script that would change my current working directory. However, any time I execute a 'cd' command in a script, it holds only for the life of that script -- the working directory on exit is the same as when the script was initiated. Is it possible to have the script return... (3 Replies)
How to change a directory on windows via perl script.
I wanna mount a share on windows via perl script.
I have used:-
system("dir");
gives the list of directories in the drive i am.This command works well.
Now i want to move from c drive to z drive via perl script.I am using:-
... (2 Replies)
Hi,
I am trying to change the directory in my script, & want to check if the directory is present or not .
Ex:
cd /home/xyz/temp/logs
if the logs directory is not present i want to show the error in script instead of shell script error.
Can anybody please help me on the same
Thx in... (2 Replies)
HI,
I need to change the working directory by using the shell script
/Export/home/user_name
I have to go one step back like
/Export/home
Please help on this.:confused: (3 Replies)
I need a script to take the filename of every file in a directory and substitute that file name for whatever is on the first line of the file. There may or may not be anything on the line, but I want the line to be the same as the file name. Most of the script tools I have used are non-destructuve,... (14 Replies)
I want to change the permission of a dir to 777 after every hour in a background process.I do not have the access to the crontab , is there another way of doing it a scrit of some thing like that . Any help will be great. (1 Reply)
Hi,
I have been trying to execute the below command by changing directory and then copying contents of one directory to another by doing some file name manipulations in between. However this isnt working since as soon as the statement completes it goes back to the original folder. Can someone... (5 Replies)
Discussion started by: HikingLife
5 Replies
LEARN ABOUT OSX
eval
eval(n) Tcl Built-In Commands eval(n)
__________________________________________________________________________________________________________________________________________________NAME
eval - Evaluate a Tcl script
SYNOPSIS
eval arg ?arg ...?
_________________________________________________________________DESCRIPTION
Eval takes one or more arguments, which together comprise a Tcl script containing one or more commands. Eval concatenates all its argu-
ments in the same fashion as the concat command, passes the concatenated string to the Tcl interpreter recursively, and returns the result
of that evaluation (or any error generated by it). Note that the list command quotes sequences of words in such a way that they are not
further expanded by the eval command.
EXAMPLES
Often, it is useful to store a fragment of a script in a variable and execute it later on with extra values appended. This technique is
used in a number of places throughout the Tcl core (e.g. in fcopy, lsort and trace command callbacks). This example shows how to do this
using core Tcl commands:
set script {
puts "logging now"
lappend $myCurrentLogVar
}
set myCurrentLogVar log1
# Set up a switch of logging variable part way through!
after 20000 set myCurrentLogVar log2
for {set i 0} {$i<10} {incr i} {
# Introduce a random delay
after [expr {int(5000 * rand())}]
update ;# Check for the asynch log switch
eval $script $i [clock clicks]
}
Note that in the most common case (where the script fragment is actually just a list of words forming a command prefix), it is better to |
use {*}$script when doing this sort of invocation pattern. It is less general than the eval command, and hence easier to make robust in |
practice. The following procedure acts in a way that is analogous to the lappend command, except it inserts the argument values at the
start of the list in the variable:
proc lprepend {varName args} {
upvar 1 $varName var
# Ensure that the variable exists and contains a list
lappend var
# Now we insert all the arguments in one go
set var [eval [list linsert $var 0] $args]
}
However, the last line would now normally be written without eval, like this: |
set var [linsert $var 0 {*}$args] |
SEE ALSO
catch(n), concat(n), error(n), interp(n), list(n), namespace(n), subst(n), tclvars(n), uplevel(n)
KEYWORDS
concatenate, evaluate, script
Tcl eval(n)