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Top Forums Shell Programming and Scripting Bash variable delayed expansion? Post 302436039 by premotheus on Friday 9th of July 2010 04:42:23 AM
Old 07-09-2010
Bash variable delayed expansion?

i write a batch file , here is the content.
Code:
dirname='date +%Y-%m-%d'
mkdir dirname

but it doen's work, it just create a folder named date and +%Y-%m-%d.
i have tried run the command seperately in the bash prompt. after the first
sentence executed , i use $dirname to watch the value of dirname ,it's right.
but how come mkdir command doesn't work?
 

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DIRNAME(1)							   User Commands							DIRNAME(1)

NAME
dirname - strip last component from file name SYNOPSIS
dirname NAME dirname OPTION DESCRIPTION
Output NAME with its last non-slash component and trailing slashes removed; if NAME contains no /'s, output `.' (meaning the current direc- tory). --help display this help and exit --version output version information and exit EXAMPLES
dirname /usr/bin/ Output "/usr". dirname stdio.h Output ".". AUTHOR
Written by David MacKenzie and Jim Meyering. REPORTING BUGS
Report dirname bugs to bug-coreutils@gnu.org GNU coreutils home page: <http://www.gnu.org/software/coreutils/> General help using GNU software: <http://www.gnu.org/gethelp/> Report dirname translation bugs to <http://translationproject.org/team/> COPYRIGHT
Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO
basename(1), readlink(1) The full documentation for dirname is maintained as a Texinfo manual. If the info and dirname programs are properly installed at your site, the command info coreutils 'dirname invocation' should give you access to the complete manual. GNU coreutils 8.12.197-032bb September 2011 DIRNAME(1)
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