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Full Discussion: [bash] Check if variable is set or blank
Top Forums Shell Programming and Scripting [bash] Check if variable is set or blank Post 302179659 by noratx on Friday 28th of March 2008 09:36:39 AM
Old 03-28-2008
[bash] Check if variable is set or blank
Hello guys.
In my script, i have the following code:
Code:
echo "The tarfile contains these directorys"
tar -tf file.tar > tarlist.txt
cat tarlist | awk -F/ '{print $1 "/" $2}' | nl
echo "Enter path of the directory you want to extract or just press enter to extract everything: "
read path
/usr/local/bin/gtar -xf file.tar $path

I need to check if the user gave a path to the script, or if he just pressed enter?
I know what to do between the 'THEN' and 'ELSE' statements.
I just need to know how to check if $path is really set or not.
 

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LEARN ABOUT LINUX

git-tar-tree

GIT-TAR-TREE(1) 						    Git Manual							   GIT-TAR-TREE(1)

NAME

       git-tar-tree - Create a tar archive of the files in the named tree object

SYNOPSIS

       git tar-tree [--remote=<repo>] <tree-ish> [ <base> ]

DESCRIPTION

       THIS COMMAND IS DEPRECATED. Use git archive with --format=tar option instead (and move the <base> argument to --prefix=base/).

       Creates a tar archive containing the tree structure for the named tree. When <base> is specified it is added as a leading path to the files
       in the generated tar archive.

       git tar-tree behaves differently when given a tree ID versus when given a commit ID or tag ID. In the first case the current time is used
       as modification time of each file in the archive. In the latter case the commit time as recorded in the referenced commit object is used
       instead. Additionally the commit ID is stored in a global extended pax header. It can be extracted using git get-tar-commit-id.

OPTIONS

       <tree-ish>
	   The tree or commit to produce tar archive for. If it is the object name of a commit object.

       <base>
	   Leading path to the files in the resulting tar archive.

       --remote=<repo>
	   Instead of making a tar archive from local repository, retrieve a tar archive from a remote repository.

CONFIGURATION

       tar.umask
	   This variable can be used to restrict the permission bits of tar archive entries. The default is 0002, which turns off the world write
	   bit. The special value "user" indicates that the archiving user's umask will be used instead. See umask(2) for details.

EXAMPLES

       git tar-tree HEAD junk | (cd /var/tmp/ && tar xf -)
	   Create a tar archive that contains the contents of the latest commit on the current branch, and extracts it in /var/tmp/junk directory.

       git tar-tree v1.4.0 git-1.4.0 | gzip >git-1.4.0.tar.gz
	   Create a tarball for v1.4.0 release.

       git tar-tree v1.4.0^{tree} git-1.4.0 | gzip >git-1.4.0.tar.gz
	   Create a tarball for v1.4.0 release, but without a global extended pax header.

       git tar-tree --remote=example.com:git.git v1.4.0 >git-1.4.0.tar
	   Get a tarball v1.4.0 from example.com.

       git tar-tree HEAD:Documentation/ git-docs > git-1.4.0-docs.tar
	   Put everything in the current head's Documentation/ directory into git-1.4.0-docs.tar, with the prefix git-docs/.

GIT

       Part of the git(1) suite

Git 1.8.5.3							    01/14/2014							   GIT-TAR-TREE(1)
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