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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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While `echo rm * | batch` might seem to work, it might still raise the load of the system since `rm` will be _started_ when the load is low, but run for a long time. My proposed command executes a new `rm` execution once every minute when the load is small.
Obviously, load could also be lower using `ionice`, but I still think this is a useful example for sequential batch jobs.
- Backup data before reszie as it over write original
-To preserve aspect ratio remove !
This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits.
An error message of the command itself is suppressed for clarity purpose.
Usually the MS-DOS cmd.exe processes in the whole FOR loop as one command and expands each var like %varname% in before (except the loop var of course).
This command enables expansion of other vars than only the loop var during the FOR loop. The syntax of the var to expand is then !varname! inside the FOR loop.
to end the setlocal command.
E.g. (only works from batch files, not from commandline directly):
FOR %%A IN (*) DO (
Loops over array of a system var, splits its values and puts the values into %A, %B, %C, %D, and so on.
Create array before, like
Be sure to replace %A, %B, etc. with %%A, %%B, etc. when using this from inside of batch files.
This command loops over all indexes of the system variable array ARRAY and puts its content into %A.
Create this array before, e.g. by
For using inside of a batch file, write %%A instead of %A.
this oneliner uses make and it's jobserver for parallel execution of your script. The '-j' flag for make defines number of subprocesses to launch, '-f' tells make use stdin instead of Makefile. Also make have neat flag '-l', which "Specifies that no new jobs (commands) should be started if there are others jobs running and the load is at least load (a floating-point number)."
Also you can use plain Makefile, for better readability:
targets = $(subst .png,.jpg,$(wildcard *.png))
echo convert $(subst .jpg,.png,$@) $@
all : $(targets)
This function does a batch edition of all OOO3 Writer files in current directory. It uses sed to search a FOO pattern into body text of each file, then replace it to foo pattern (only the first match) . I did it because I've some hundreds of OOO3 Writer files where I did need to edit one word in each ones and open up each file in OOO3 gui wasn't an option. Usage: bsro3 FOO foo
Resizes all images in the curent directory to x resolution.
It is better than `mogrify -resize *.jpg` because of independence from extension of image (e.g. .jpg and .JPG) (:
This command requires the imagemagick libraries and will resize all files with the .jpg extension to a width of 1024 pixels and will keep the same proportions as the original image.