9 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I'm using this form of variable setting to use the exit status of a pipeline e.g.
foo=$(date|grep -i thursday)$?
echo $foo
echo ${PIPESTATUS}
or $foo later in a script.
On days other than Thursday it results in:
1
0
For some reason the PIPESTATUS array doesn't show.
I'd... (2 Replies)
Discussion started by: spacegoose
2 Replies
2. Shell Programming and Scripting
anyone has any info on why this is complaining???
vivek@vivek-c5e55ef2e ~/TAC
$ zoneCounter=1
vivek@vivek-c5e55ef2e ~/TAC
$ optUsage1=23%
vivek@vivek-c5e55ef2e ~/TAC
$ eval eval echo "<th>Zone $zoneCounter </th><th align=\"left\"> \$optUsage$zoneCounter </th>"
-bash: syntax error... (13 Replies)
Discussion started by: vivek d r
13 Replies
3. Shell Programming and Scripting
anyone has any info on why this is complaining???
vivek@vivek-c5e55ef2e ~/TAC
$ zoneCounter=1
vivek@vivek-c5e55ef2e ~/TAC
$ optUsage1=23%
vivek@vivek-c5e55ef2e ~/TAC
$ eval eval echo "<th>Zone $zoneCounter </th><th align=\"left\"> \$optUsage$zoneCounter </th>"
-bash: syntax error... (1 Reply)
Discussion started by: vivek d r
1 Replies
4. Fedora
Hey guys,
Not sure if this is the best place for this question, but, after using Fedora now for about a year, I'm still getting used to it but I'm using it practically all the time now and instead of having a dual boot with Windows 7, I want to create an image of my Windows 7 installation,... (3 Replies)
Discussion started by: jimbob01
3 Replies
5. Shell Programming and Scripting
Hi all,
some small script with eval turned me to crazy.
my OS is linux
Linux s10-1310 2.6.16.53-0.8.PTF.434477.3.TDC.0-smp #1 SMP Fri Aug 31 06:07:27 PDT 2007 x86_64 x86_64 x86_64 GNU/Linux
below script works well
#!/bin/bash
eval ssh remotehost date
eval ssh remotehost ls
below... (1 Reply)
Discussion started by: summer_cherry
1 Replies
6. Shell Programming and Scripting
I am trying to create a service to always run and monitor a script that has a tendency to hang, we could not find what is causing it to hang so are in the process of completely reprogramming just about everything, however, that will take upto 6 months.
So I need to create this to monitor the... (5 Replies)
Discussion started by: ukndoit
5 Replies
7. Shell Programming and Scripting
Hi,
Can someone help me with creating a bash shell script.
I need to create a script that gets a positive number n as an argument.
The script must create n directories in the current directory with names like map_1, map_2 etcetera. Each directory must be contained within its predecessor. So... (7 Replies)
Discussion started by: I-1
7 Replies
8. Shell Programming and Scripting
Hi,
I have to create a sheduler to run the shell scripts one by one(dependency).
Suppose i have 10 scripts.
For all the 10 scripts i have a database table containing these scripts_names and status.
Executing the first script.if the first status script is only 'success' then go to next... (4 Replies)
Discussion started by: laknar
4 Replies
9. UNIX for Dummies Questions & Answers
I havn't installed solaris 10 (nor any solaris in a long time). I noticed that during the install the file system layout allowed me to create a swap partition, but there wern't enough partitions to create a /var/run (I am mirroring the disk config of another system). Is /var/run created manually... (2 Replies)
Discussion started by: csgonan
2 Replies
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)