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Top Forums Shell Programming and Scripting How to build a command into a string rather than execute the command Post 302200671 by littlejon on Thursday 29th of May 2008 07:31:45 PM
Old 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..
 

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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)
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