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Full Discussion: Bash shell expansion help
Top Forums Shell Programming and Scripting Bash shell expansion help Post 302955503 by cokedude on Thursday 17th of September 2015 10:13:14 PM
Old 09-17-2015
Bash shell expansion help
This is what I have in my directory.

Code:
$ ls
test1.txt  test2.txt  test3.txt  test4.txt  test5.txt  test_script.sh

This is what my shellscript looks like.

Code:
#!/bin/bash

for  filename in /shell_expansion/*.txt; do
           for ((i=0; i<=3; i++)); do
               echo "$filename"
           done
done

This is what happens when I run my shellscript.

Code:
./test_script.sh
/shell_expansion/*.txt
/shell_expansion/*.txt
/shell_expansion/*.txt
/shell_expansion/*.txt

I don't understand why shell expansion isn't happening on the *. Why am I getting /shell_expansion/*.txt instead of /shell_expansion/test1.txt and so on?
 

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LEARN ABOUT DEBIAN

rdup-up

RDUP-UP(1)							       rdup								RDUP-UP(1)

NAME

       rdup-up - update a directory tree with a rdup archive

SYNOPSIS

       rdup-up [OPTION]...  DIRECTORY

DESCRIPTION

       With rdup-up you can update an (possibly) existing directory structure with a rdup archive.

       The rdup archive has to be given to rdup-up's standard input.

   Username and uids
       rdup  outputs  both  the  username  and	uid, the receiving system (which may be a totally different system) checks if the username and uid
       match. If the username and uid don't match the (numeric) uid is used on the file. The same holds true for the groupname and gid.

OPTIONS

       -n     Do a dry-run and do not create anything on disk.

       -t     Create DIRECTORY (ala mkdir -p) if it does not exist.

       -s N   Strip N path components from a pathname. If the resulting pathname is empty after this operation it is skipped. Be  careful  however
	      with the following structure:

		  /foo
		  /foo/bar
		  /foo/bar/bla.txt
		  /foo/blork/bla.txt

	      With rdup-up -s2 this will leave:

		  <empty>
		  <empty>
		  /bla.txt
		  /bla.txt

	      And the last 'bla.txt' will overwrite the previous one, this will happen without warnings.

       -r PATH
	      This option is related to the -s option, but works different. The string PATH is removed from (the beginning of) each pathname. With
	      -r /home/backup the pathname /home/backup/bin/mycmd becomes /bin/mycmd. The same could be done with -s 2, but then you need to count
	      the slashes. Note -s is always performed before -r.

       -v     Be more verbose and echo the processed files to standard output.

       -vv    Be even more verbose and echo processed file and the uid and gid information to standard output.

       -T     Show  a  table  of  contents of the rdup stream received (ala tar -tf -).  With -T the directory argument is optional. -T unsets any
	      verbose (-v) options.

       -h     A short help message.

       -V     Show the version.

EXIT CODE

       rdup-up return a zero exit code on success, otherwise 1 is returned.

AUTHOR

       Written by Miek Gieben.

REPORTING BUGS

       Report bugs to <miek@miek.nl>.

SEE ALSO

       http:/www.miek.nl/projects/rdup/ is the main site of rdup. Also see rdup(1), rdup-tr(1) and rdup-backups(7).

COPYRIGHT

       Copyright (C) 2005-2010 Miek Gieben. This is free software. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A	PARTICULAR
       PURPOSE.

       Licensed under the GPL version 3. See the file LICENSE in the source distribution of rdup.

1.1.11								    13 Dec 2008 							RDUP-UP(1)
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