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Make sure that find does not touch anything other than regular files, and handles non-standard characters in filenames while passing to xargs.
needs no GNU tools, as far as I see it
This has helped me numerous times trying to find either log files or tmp files that get created after execution of a command. And really eye opening as to how active a given process really is. Play around with -anewer, -cnewer & -newerXY
get diskusage of files (in this case logfiles in /var/log) modified during the last n days:
sudo find /var/log/ -mtime -n -type f | xargs du -ch
n -> last modified n*24 hours ago
Numeric arguments can be specified as
+n for greater than n,
-n for less than n,
n for exactly n.
=> so 7*24 hours (about 7 days) is -7
sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1
1. find file greater than 10 MB
2. direct it to xargs
3. xargs pass them as argument to ls
this command works with one gziped file per table, and restore 4 tables in parallel.
This command changes all filename and directories within a directory tree to unaccented ones. I had to do this to 'sanitize' some samba-exported trees. The reason it works might seem a little difficult to see at first - it first reverses-sort by pathname length, then it renames only the basename of the path. This way it'll always go in the right order to rename everything.
Some notes:
1. You'll have to have the 'unaccent' command. On Ubuntu, just aptitude install unaccent.
2. In this case, the encoding of the tree was UTF-8 - but you might be using another one, just adjust the command to your encoding.
3. The program might spit a few harmless errors saying the files are the same - not to fear.
Sqlite database keeps collecting cruft as time passes, which can be cleaned by the 'vacuum;' command. This command cleans up the cruft in all sqlite files relating to the user you have logged in as. This command has to be run when firefox is not running, or it will exit displaying the pid of the firefox running.
Alter "AddHandler php5-cgi .php" and "AddHandler php4-cgi .php" entries to new "AddHandler x-httpd-php5 .php" respective php4 entries in all .htaccess files under /var/www
The `-q' arg forces tail to not output the name of the current file
Character: "?" is the Byte Order Mark (BOM) of the Unicode Standard.
Specifically it is the hex bytes EF BB BF, which form the UTF-8 representation of the BOM,
misinterpreted as ISO 8859/1 text instead of UTF-8.
I used this to copy all PDFs recursively to a selected dir
Using a GUI file managers you can merge directories (cut and paste). This command roughly does the same (it doesn't ask for confirmation (no problem for me) and it doesn't clean up the empty SRC directories (no problem, trivial).
probably does the same:
cp -l SRC TARGET; rm -rf SRC
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.
Best to put it in a file somewhere in your path. (I call the file spath)
#!/bin/bash
IFS=:; find $PATH | grep $1
Usage: $ spath php
This command will find the biggest files recursively under a certain directory, no matter if they are too many. If you try the regular commands ("find -type f -exec ls -laSr {} +" or "find -type f -print0 | xargs -0 ls -laSr") the sorting won't be correct because of command line arguments limit.
This command won't use command line arguments to sort the files and will display the sorted list correctly.