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Full Discussion: cp output /dev/null results in not a directory
Top Forums UNIX for Dummies Questions & Answers cp output /dev/null results in not a directory Post 302318548 by stevesmo on Thursday 21st of May 2009 10:03:55 PM
Old 05-21-2009
cp output /dev/null results in not a directory
Hello,
I am working on a script to measure the read performance of a busybox environment. The logical choice is to use a command line like:

(time cp * /dev/null) 2> /tmp/howlong.txt

Ah, the rub is cp or /dev/null will only accept a single file at a time.
The result in the txt file is and output list that basically shows /dev/null/filename Not a directory.

I tried the same with using dd if=* of=/dev/null bs=1M, alas the results were similar.

I tried using a for loop, but I could not get time to work with syntax errors.

Example:

Works:
for FILE * cp $FILE /dev/null ; done

Fails:
(time for FILE * cp $FILE /dev/null ; done) 2> /tmp/howlong.txt

Any help here would be appreciated.
Thanks,

-Steve
 

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LEARN ABOUT OPENSOLARIS

dev

dev(7FS)							   File Systems 							  dev(7FS)

NAME

       dev - Device name file system

DESCRIPTION

       The  dev  filesystem  manages  the  name  spaces  of devices under the Solaris operating environment. The global zone's instance of the dev
       filesystem is mounted during boot on /dev.

       A subdirectory under /dev may have unique operational semantics. Most of the common device names under /dev are	created  automatically	by
       devfsadm(1M).   Others,	such  as  /dev/pts,  are dynamic and reflect the operational state of the system. You can manually generate device
       names for newly attached hardware by invoking devfsadm(1M) or implicitly, by indirectly causing	a  lookup  or  readdir	operation  in  the
       filesystem to occur.  For example, you can discover a disk that was attached when the system was powered down (and generate a name for that
       device) by invoking format(1M)).

FILES

       /dev    Mount point for the /dev filesystem in the global zone.

SEE ALSO

       devfsadm(1M), format(1M), devfs(7FS)

NOTES

       The global /dev instance cannot be unmounted.

SunOS 5.11							    9 June 2006 							  dev(7FS)
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