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Full Discussion: Why is ./ sometimes needed?
Top Forums Shell Programming and Scripting Why is ./ sometimes needed? Post 303029716 by Don Cragun on Thursday 31st of January 2019 06:25:26 AM
Old 01-31-2019
Quote:
Originally Posted by wisecracker
Hi Don...


Check your double quotes, some have one too many.
And just as an addendum, from 'shellcheck', see attached image...
Hi wisecracker,
Thank you for catching the mismatched double-quotes. I was trying to change "$var"/string to "$var/string" and didn't complete the job in a couple of lines.

I'm sorry that shellcheck doesn't like stand-alone redirections. They are part of the shell command language and there is no need to combine them with another command when used as they are used in the script being discussed in this thread.

Note also that the commands:
Code:
true > "${LOG_DIR}/message"
true > "${LOG_DIR}/wtmp"

produces the same results in the script being discussed in this thread but runs slower and just like:
Code:
> "${LOG_DIR}/message"
> "${LOG_DIR}/wtmp"

will give a zero exit status even when > "${LOG_DIR}/message" failed if > "${LOG_DIR}/wtmp" succeeded.

Of course, the discussion would be different if other pipelines that send output to standard output without redirecting that output were to be included in the script after these redirections; but that isn't the case here in cleanup2. Nonetheless, I should have stated this assumption in the example I provided.
These 2 Users Gave Thanks to Don Cragun For This Post:
wisecracker Xubuntu56
 

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LEARN ABOUT DEBIAN

glance-cache-prefetcher

GLANCE-CACHE-PREFETCHER(1)					      Glance						GLANCE-CACHE-PREFETCHER(1)

NAME

       glance-cache-prefetcher - Glance Cache Pre-fetcher

GLANCE IMAGE CACHE PRE-FETCHER
       Author glance@lists.launchpad.net

       Date   2012-01-03

       Copyright
	      OpenStack LLC

       Version
	      2012.1-dev

       Manual section
	      1

       Manual group
	      cloud computing

   SYNOPSIS
	  glance-cache-prefetcher [options]

   DESCRIPTION
       This is meant to be run from the command line after queueing images to be pretched.

   OPTIONS
	  --version
		 show program's version number and exit

	  -h, --help
		 show this help message and exit

	  --config-file=PATH
		 Path  to a config file to use. Multiple config files can be specified, with values in later files taking precedence.  The default
		 files used are: []

	  -d, --debug
		 Print debugging output

	  --nodebug
		 Do not print debugging output

	  -v, --verbose
		 Print more verbose output

	  --noverbose
		 Do not print verbose output

	  --log-config=PATH
		 If this option is specified, the logging configuration file specified is used and overrides any other logging options	specified.
		 Please see the Python logging module documentation for details on logging configuration files.

	  --log-format=FORMAT
		 A logging.Formatter log message format string which may use any of the available logging.LogRecord attributes.  Default: none

	  --log-date-format=DATE_FORMAT
		 Format string for %(asctime)s in log records.	Default: none

	  --log-file=PATH
		 (Optional) Name of log file to output to. If not set, logging will go to stdout.

	  --log-dir=LOG_DIR
		 (Optional) The directory to keep log files in (will be prepended to --logfile)

	  --use-syslog
		 Use syslog for logging.

	  --nouse-syslog
		 Do not use syslog for logging.

	  --syslog-log-facility=SYSLOG_LOG_FACILITY
		 syslog facility to receive log lines

   SEE ALSO
       o OpenStack Glance

   BUGS
       o Glance is sourced in Launchpad so you can view current bugs at OpenStack Glance

AUTHOR

       OpenStack

COPYRIGHT

       2010-present, OpenStack, LLC.

2012.1.1							  March 14, 2013					GLANCE-CACHE-PREFETCHER(1)
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