Commands by tatwright (6)

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clone directory structure
dir1 and all its subdirs and subdirs of subdirs ... but *no files* will be copied to dir2 (not even symbolic links of files will be made). To preserve ownerships & permissions: $ cp -Rps dir1 dir2 Yes, you can do it with $ rsync -a --include '*/' --exclude '*' /path/to/source /path/to/dest too, but I didn't test if this can handle attributes correctly (experiment rsync command yourself with --dry-run switch to avoid harming your file system) You must be in the parent directory of dir1 while executing this command (place dir2 where you will), else soft links of files in dir2 will be made. I couldn't find how to avoid this "limitation" (yet). Playing with recursive unlink command loop maybe? PS. Bash will complain, but the job will be done.

Create a backdoor on a machine to allow remote connection to bash
My netcat (nc-1.84-10.fc6) doesn't have the -e option, so I have to do it like this. Of course, instead of bash, you can use any executable, including scripts.

use wget to check if a remote file exists

Use the builtin ':' bash command to increment variables
I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

Print one . instead of each line
this version only uses shell builtins

automatically ditch old versions in a conflict
This is not exactly a commandline, but a vim macro to automatically ditch the "old" version of a conflict when dealing with the naster

Print the IPv4 address of a given interface

Converts uppercase chars in a string to lowercase

seq can produce the same thing as Perl's ... operator.
Optionally, one can use {1..50} instead of seq. E.g. for i in {1..50} ; do echo Iteration $i ; done

return a titlecased version of the string[str.title() in python]


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