Commands by alcik (4)

  • You can use wildcard with rpm search but you have to do 2 things: 1. use "-a" switch (means "all") with query ("-q") switch - argument is a pattern to use while searching for package names of all installed packages 2. protect wildcards, so that shell could not eat them - escape it with backslash ("\") or enclose all pattern between apostrophes ("'"): rpm -qa 'co*de' As you can see above it is possible to insert wildcards into middle of the pattern. If you want, you can add "-i" or another rpm query options, "-i" will print package information for all installed packages matching pattern. Show Sample Output


    2
    rpm -qa \*code\*
    alcik · 2009-03-11 21:16:23 3
  • This example summarize size of all pdf files in /tmp directory and its subdirectories (in bytes). Replace "/tmp" with directory path of your choice and "\*pdf" or even "-iname \*pdf" with your own pattern to match specific type of files. You can replace also parameter for du to count kilo or megabytes, but because of du rounding the sum will not be correct (especially with lot of small files and megabytes counting). In some cases you could probably use sth like this: du -cb `find /tmp -type f -iname \*pdf`|tail -n 1 But be aware that this second command CANNOT count files with spaces in their names and it will cheat you, if there are some files matching the pattern that you don't have rights to read. The first oneliner is resistant to such problems (it will not count sizes of files which you cant read but will give you correct sum of rest of them). Show Sample Output


    0
    SUM=0; for FILESIZE in `find /tmp -type f -iname \*pdf -exec du -b {} \; 2>/dev/null | cut -f1` ; do (( SUM += $FILESIZE )) ; done ; echo "sum=$SUM"
    alcik · 2009-03-05 17:16:52 4
  • It displays, last 15 yum operations (in last operation as first row order) with its dates. Change 15 to any number of operations you need to display or remove "| tac" to see it in reverse order (last operation as last row)


    0
    tail -n 15 /var/log/yum.log | tac
    alcik · 2009-03-02 08:56:04 1
  • Replace 'more' command with any command which is in your PATH. Show Sample Output


    3
    rpm -qif `which more`
    alcik · 2009-02-27 08:59:07 3

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Install pip with Proxy
Installs pip packages defining a proxy

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Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

generate random password (works on Mac OS X)
Prepending env LC_CTYPE=C fixes a problem with bad bytes in /dev/urandom on Mac OS X

Find how far nested you are in subshells

grep for minus (-) sign
Use flag "--" to stop switch parsing

Show the UUID of a filesystem or partition
Shows the UUID of a filesystem or partition that can be used in kernel root options and in fstab. Run it without the -u option to generate more information. eg: ~/ sudo vol_id /dev/sda2 ID_FS_USAGE=other ID_FS_TYPE=swap ID_FS_VERSION=2 ID_FS_UUID=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_UUID_ENC=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_LABEL= ID_FS_LABEL_ENC=

drop first column of output by piping to this
An advantage is that this doesn't modify remained string at all. One can change {0,1} with {0,n} to drop several columns

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Sum size of files returned from FIND


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