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Full Discussion: need help understanding mv
Top Forums Shell Programming and Scripting need help understanding mv Post 302357037 by cfajohnson on Monday 28th of September 2009 01:05:44 PM
Old 09-28-2009
Quote:
Originally Posted by methyl
To cfajohnson. I did not expect this response from you who I recognise as an expert in shell syntax. The O/P script did not contain the problem, my initial response did not contain the problem, but the example was designed to teach.

Please explain the error message in my example in your own words.

I was not commenting on any error message. I was answering the question, "Can you briefly explain the curly brackets."

My comment was about this:

Code:
mv "${file1}" "${file1}.TMP"
mv "${file2}" "${file2}.TMP"

The braces are not necessary in that example. They are not wrong, but they do nothing.

If the example had been:

Code:
mv "${file1}" "${file1}_TMP"
mv "${file2}" "${file2}_TMP"

...then they would have been necessary but only in the second instance on each line.
 

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LEARN ABOUT DEBIAN

suspend

suspend(1)                                                         User Commands                                                        suspend(1)

NAME

       suspend - shell built-in function to halt the current shell

SYNOPSIS

   sh
       suspend

   csh
       suspend

   ksh
       suspend

DESCRIPTION

   sh
       Stops the execution of the current shell (but not if it is the login shell).

   csh
       Stop the shell in its tracks, much as if it had been sent a stop signal with ^Z. This is most often used to stop shells started by su.

   ksh
       Stops the execution of the current shell (but not if it is the login shell).

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Availability                 |SUNWcsu                      |
       +-----------------------------+-----------------------------+

SEE ALSO

       csh(1), kill(1), ksh(1), sh(1), su(1M), attributes(5)

SunOS 5.10                                                          15 Apr 1994                                                         suspend(1)
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