05-29-2008
How to build a command into a string rather than execute the command
I'm trying to populate a command line into a variable. It appears to be executing, instead. Here's an example:
mycmd=''
if ...; then
$mycmd='sudo '
fi
$mycmd=$mycmd 'sed -i prev s/aaa/bbb/' $myfile
res=`$mycmd`
(I'm also not sure of the best way to execute the command from the variable, either, so any corrections would be appreciated!)
Last edited by littlejon; 05-29-2008 at 08:56 PM..
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hi Group ,
I m trying to execute commands on some other system using write command but inspite of executing the commands they r passed as simple messages.
- i m writing
>write user-id
! ls
o
ctrl-d
inspite of executing the command ls,other terminal shows ! ls.
Thnx in advance. (2 Replies)
Discussion started by: Aashish
2 Replies
2. Shell Programming and Scripting
my description from another thread...
here's my code:
#!/bin/bash
IFS=$'\n'
function OutputName() {
input=$1
echo $input
input=`echo "$input" | sed -e 's/.//'`
input=`echo "$input".avi`
output_name=$input
}
if ]; then
echo... (5 Replies)
Discussion started by: TinCanFury
5 Replies
3. Shell Programming and Scripting
I am using an array to store some data (keys e.g 47975081_1215781266128), it can be assumed that it is key to other data.
I want extract data from a file based on a couple of keys (range) and store the resulting data in a variable using the following command:
sed -n... (9 Replies)
Discussion started by: gugs
9 Replies
4. Shell Programming and Scripting
Hello everyone.
I am using the select command to build a menu, here is my question:
Is it possible to generate a menu which contains several sections and have a separator between the sections without having a selection number generated in front of the separator?
This is a sample of what I would... (1 Reply)
Discussion started by: gio001
1 Replies
5. Shell Programming and Scripting
Hi All
I am trying to build a script that will take data from a tab separated file and use that to split up a quicktime file. So far the code is as follows
#!/bin/sh
#test parsing of data
#fix excel file output returns
cat $1 | tr "\r" "\n" > $1.fix
printf "\n" >> $1.fix
mv $1.fix $1
... (3 Replies)
Discussion started by: babajuma
3 Replies
6. Shell Programming and Scripting
Hi,
Here's the problem I am facing.
This is just an example:
list_files.ksh
------------
dir=$1
match=$2
var="ls $dir | grep $match"
files=`"$var"`
I get the below error on executing the above script:
./list_files.ksh: ls /home/my_files | grep xml: not found
I know I... (2 Replies)
Discussion started by: dips_ag
2 Replies
7. Shell Programming and Scripting
I am running the export command within a view to use that value inside my build script. But while executing it it is saying "export command not found"
My code is as follows:
--------------------------
#!/bin/sh
user="test"
DIR="/bldtmp/"$user
VIEW="test.view1"
echo "TMPDIR before export... (4 Replies)
Discussion started by: dchoudhury
4 Replies
8. Shell Programming and Scripting
Hi Experts,
I am very much new to linux scripting, I am currently working on reducing my manual work and hence writing a script to automate few task.
I am running below command to snmpwalk the router..
snmpwalk -v 3 -u WANDL_SU -a MD5 -A vfipmpls -x DES -X VfIpMpLs -l authPriv... (19 Replies)
Discussion started by: Hanumant.madane
19 Replies
9. Shell Programming and Scripting
Hello :)
new to bash not to programming.
I have an on-going need to change the owning group on sets of files and directories from the one they were created with or changed to on update to the one they need to have going forward.
find {target_root} -group wrong_group
gets me a newline... (4 Replies)
Discussion started by: naftali
4 Replies
10. Shell Programming and Scripting
Hello i am having an issue with bash script and this is the code
now=$(cat hosts1.txt | awk '{print $2;}')
while read n ;do
ssh root@$now 'useradd test1; echo -e "test1\ntest1" | passwd test1 && echo "test1 ALL=(ALL:ALL) ALL" >> /etc/sudoers'
When i execute only part with cat, it... (8 Replies)
Discussion started by: tomislav91
8 Replies
prev(1) General Commands Manual prev(1)
NAME
prev - show the previous message (only available within the message handling system, mh)
SYNOPSIS
prev [+folder] [-[no]header] [-help] [-showproc program] [-noshowproc] [options to showproc]
OPTIONS
Displays a one-line header before the message. The header consists of the name of the folder and the message number. This is the default
behavior. It can be suppressed with the -noheader option. Prints a list of the valid options to this command. Specifies an alternative
program to list messages. The default is to use the program defined by the showproc: entry in the file. As with show, you can give options
to the showproc program at the command line. These are passed directly to showproc by prev.
The defaults for this command are:
+folder defaults to the current folder -header
DESCRIPTION
The prev command displays the previous message in the current folder. The previous message is the one before the current message in the
folder. The message that is shown becomes the current message.
You can specify a folder other than the current folder by using the +folder argument. If you specify a folder, that becomes the current
folder.
RESTRICTIONS
The prev command is really a link to the show program. As a result, if you make a link to prev and that link is not called prev, your link
will act like show instead. To avoid this, add a profile-entry for the link to your MH profile and add the argument prev to the entry.
PROFILE COMPONENTS
Path: To determine your Mail directory
showproc: Program to show the message
EXAMPLES
The command in the following example displays the previous message in the folder +copylog: $ prev +copylog
FILES
The user profile.
SEE ALSO
show(1), next(1)
prev(1)