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greps your bash history for whatever you type in at the end returning it in reverse chronological order (most recent invocations first), should work on all distros.
works well as an alias
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.
The same thing using only Bash built-in's.
For readability I've kept the variables out, but it could me made extremely more compact (and totally unreadable!) by stuffing everything inside the single echo command.
This is *NOT* about the -i option in grep. I guess everybody already knows that option. This is about the basic rule of life that the simplest things are sometimes the best. ;-)
One day when I used "grep -i" for the umpteenth time, I decided to make this alias, and I've used it ever since, probably more often than plain grep. (In fact I also have aliases egrip and fgrip defined accordingly. I also have wrip="grep -wi" but I don't use this one that often.)
If you vote this down because it's too trivial and simplistic, that's no problem. I understand that. But still this is really one of my most favourite aliases.
Lists crontab for all users on system that have crontabs.
Replaces tabs in output with spaces. Uses perl since sed seems to work differently across platforms.
Replace FILE with a filename (or - for stdin).
Shows a single line per interface (device), with its IPv4 settings.
Shorter command, better readability in output.
After you install slocate ,the first thing you have to do with it to initialise the database by issuing a command " slocate -u" . And then onwards just give the filename or dirname as a argument to the slocate command will reveal the files/dirs location in the system along with path.Moreover over it's an securely way of looking into the file system.
file displays a files type
the -L flag means follow sym-links (as libraries are often sym-linked to another this behavior is likely preferred)
more complex behavior (*two* grep commands!) could be used to determine if the file is or is not a shared library.
Now a bit of explanation required for this command.Once you type the command it opens up an vi editor with an temporary file enlisting the password file information .So if you make an change it will not reflected in the passwd file until you save the file.The reason behind using this command over other way to view the password file in network environment is that it locks the password file when you start working with it.So no one can temper with it during that period.Once you are done(means you save the tmp file) ,it will release the lock associated with it.I think it's a better mechanism to view the sensitive data like passwd file.Never ever use other tool like cat, nano or any other means.
In bash, by pressing ALT+n and then a character x, x will be printed n times
I know is not the same as the original command, but is correlated.
For those days when you need to know if something is happening because the day ends in "y".
If you follow my previous posting regarding "vipw" then no explanation required.The same method goes behind this command also.It will open an tmp file in vi editor to give you the enlisting to edit the group file.And most importantly to attach a lock with it.Once you are done ,the lock is released and the changed reflected to the original file.So you can securely edit the group file over the network without the fear of being tampered .
Good if you have your music like Artist/(Year) Album/Song
If you follow my other posting regarding "vipw" and "vigr' then no explanation required.It has done the same thing as did with those two command.Open the /etc/sudoers file and attach a lock with it. Once you are done with it ,the lock gets released and the changes reflected to the original file.It will open a tmp file in vi editor to give you the chance to edit the sudoers file securely.visudo parses the sudoers file after the edit and will not save the changes if there is a syntax error. Upon finding an error, visudo will print a message stating the line number(s) where the error occurred and the user will receive the "What now?" prompt. At this point the user may enter "e" to re-edit the sudoers file, "x" to exit without saving the changes, or "Q" to quit and save changes. The "Q" option should be used with extreme care because if visudo believes there to be a parse error, so will sudo and no one will be able to sudo again until the error is fixed. If "e" is typed to edit the sudoers file after a parse error has been detected, the cursor will be placed on the line where the error occurred (if the editor supports this feature).
PS: Although I have had experienced myself and few people shown to me that it behaves badly in some distribution ,noteably SLES.But the problem can be rectified with little caution.
This is quite usefull in Unix system share via NFS or AppleTalk with OSX clients that like to populate your filesystem with these pesky files
Once it is connected to the remote server by that ssh protocol,the mentioned command will start working on that server.