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Top Forums Shell Programming and Scripting Bash syntax behaviour : [[ vs [ Post 302881093 by jcdole on Thursday 26th of December 2013 01:59:33 PM
Old 12-26-2013
[SOLVED] Bash syntax behaviour : [[ vs [

Quote:
Originally Posted by Scrutinizer
In the case of single brackets, pathname expansion does get performed, however in the case of double brackets this is not the case, so in your example with single brackets after variable expansion of $RESTORE_FF.* to a_file.tar.gz.*, the pathname pattern gets expanded to a_file.tar.gz., so it would look for the literal file a_file.tar.gz. and in the case of double brackets for the literal file a_file.tar.gz.*, which does not exist. The example with single brackets will give a syntax error if more than one file with the given pattern exists.
Thank you very much.

Last edited by jcdole; 12-26-2013 at 03:04 PM..
 

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IS_DIR(3)								 1								 IS_DIR(3)

is_dir - Tells whether the filename is a directory

SYNOPSIS
bool is_dir (string $filename) DESCRIPTION
Tells whether the given filename is a directory. PARAMETERS
o $filename - Path to the file. If $filename is a relative filename, it will be checked relative to the current working directory. If $file- name is a symbolic or hard link then the link will be resolved and checked. If you have enabled safe mode, or open_basedir further restrictions may apply. RETURN VALUES
Returns TRUE if the filename exists and is a directory, FALSE otherwise. EXAMPLES
Example #1 is_dir(3) example <?php var_dump(is_dir('a_file.txt')); var_dump(is_dir('bogus_dir/abc')); var_dump(is_dir('..')); //one dir up ?> The above example will output: bool(false) bool(false) bool(true) ERRORS
/EXCEPTIONS Upon failure, an E_WARNING is emitted. NOTES
Note The results of this function are cached. See clearstatcache(3) for more details. Tip As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to "Supported Protocols and Wrappers" to determine which wrappers support stat(3) family of functionality. SEE ALSO
chdir(3), dir(3), opendir(3), is_file(3), is_link(3). PHP Documentation Group IS_DIR(3)
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