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 18
  • 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 8
  • 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 6
  • 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 11

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Show a Package Version on RPM based distributions
if you want to see all information about a package use: rpm -qi pkgname full list of querytags can be accessed by the command: rpm --querytags you can also customize the query format how ever you like with using more querytags together along with escape sequences in "man printf"! you can also use more than one package name. for example this command shows name and version in to columns: rpm -q --queryformat %-30{NAME}%{VERSION}\\n pkg1 pkg2

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Decode base64-encoded file in one line of Perl
Another option is openssl.

Find biggest 10 files in current and subdirectories and sort by file size

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Decode base64-encoded file in one line of Perl
If you are in an environment where you don't have the base64 executable or MIME tools available, this can be very handy for salvaging email attachments when the headers are mangled but the encoded document itself is intact.

old man's advice

Temporarily ignore known SSH hosts
you may create an alias also, which I did ;-) alias sshu="ssh -o UserKnownHostsFile=/dev/null "

Get each users commit amount


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