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Full Discussion: Interpreting Logicals/Environment Variables using the read command
Top Forums Shell Programming and Scripting Interpreting Logicals/Environment Variables using the read command Post 302320196 by kingpin2502 on Wednesday 27th of May 2009 09:58:35 AM
Old 05-27-2009
Interpreting Logicals/Environment Variables using the read command
Hi All

I have something that from the outset seems really trivial but in practice is not quite working.

I have the following code sample in my shell script which illustrates the problem

Code:
echo "enter home directory"
read home
mkdir $home/newdir

The user then enters a logical $HOME in the prompt. This is what is displayed on the screen

Code:
enter home directory
$HOME
mkdir: cannot create directory `$HOME/newdir': No such file or directory

If I type the full name into the prompt, it works fine. But this isn't ideal as in the real script, the directory structure could be 10 directories deep. Typing the full path could lead to potential issues.

Is there some way for the read command to interpret environment variables?

Thanks
 

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LEARN ABOUT HPUX

mvdir

mvdir(1M)																 mvdir(1M)

NAME

       mvdir - move a directory

SYNOPSIS

       dir newdir

DESCRIPTION

       moves one directory tree into another existing directory (within the same file system), or renames a directory without moving it.

       dir must be an existing directory.

       If newdir does not exist but the directory that would contain it does, dir is moved and/or renamed to newdir.  Otherwise, newdir must be an
       existing directory not already containing an entry with the same name as the last pathname component of dir.  In this case,  dir  is  moved
       and becomes a subdirectory of newdir.  The last pathname component of dir is used as the name for the moved directory.

       refuses	to  move  dir  if  the	path specified by newdir would be a descendent directory of the path specified by dir.	Such cases are not
       allowed because cyclic sub-trees would be created as in the case, for example, of which is prohibited.

       does not allow directory to be moved.

       Only users who have appropriate privileges can use

EXTERNAL INFLUENCES

   International Code Set Support
       Single- and multi-byte character code sets are supported.

AUTHOR

       was developed by OSF and HP.

SEE ALSO

       cp(1), mkdir(1), mv(1).

STANDARDS CONFORMANCE

																	 mvdir(1M)
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