Commands by argv (21)


  • 1
    case `uname` in FreeBSD)a=$#; case $a in 2) case $1 in 0) jot $(($2+1)) 0 $2 ;; *) jot $2 $1 $2 ;;esac;esac;esac; # usage: seq 1 4; seq 0 4
    argv · 2012-07-18 22:07:39 1
  • usage: dng BRE [selection] default selection is the last match DNS is ok, but although domainnames may be easier to remember than IP numbers, it still requires typing them out. This can be error-prone. Even more so than typing IPv4 numbers, depending on the domainname, its length and complexity.


    0
    dng(){ local a;a=$(sed '/'"$1"'/!d' /etc/hosts |sed '=;'"${2-1,$}"'!d'|sed '/ /!d');echo $a|tr '\040' '\n'|nl -bp'[0-9]$'|less -E;export dn=$(echo $a|sed 's,.* ,,');export ip=$(echo $a|sed 's, .*,,');echo \$dn=$dn;echo \$ip=$ip;}
    argv · 2012-04-01 23:57:09 0
  • proc lister usage: p proc killer usage: p patt [signal] uses only ps, grep, sed, printf and kill no need for pgrep/pkill (not part of early UNIX) _p(){ ps ax \ |grep $1 \ |sed ' /grep.'"$1"'/d' \ |while read a;do printf ${a%% *}' '; printf "${a#* }" >&2; printf '\n'; done; } p(){ case $# in 0) ps ax |grep .|less -iE; ;; 1) _p $1; ;; [23]) _p $1 2>/dev/null \ |sed '/'"$2"'/!d; s,.*,kill -'"${3-15}"' &,'|sh -v ;; esac; } alas, can't get this under 255 chars. flatcap? Show Sample Output


    0
    _p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
    argv · 2012-04-01 19:46:19 1
  • proc lister usage: p proc killer usage: p patt [signal] uses only ps, grep, sed, printf and kill no need for pgrep/pkill (not part of early UNIX) _p(){ ps ax \ |grep $1 \ |sed ' /grep.'"$1"'/d' \ |while read a;do printf ${a%% *}' '; printf "${a#* }" >&2; printf '\n'; done; } p(){ case $# in 0) ps ax |grep .|less -iE; ;; 1) _p $1; ;; [23]) _p $1 2>/dev/null \ |sed '/'"$2"'/!d; s,.*,kill -'"${3-15}"' &,'|sh -v ;; esac; } alas, can't get this under 255 chars. flatcap? Show Sample Output


    0
    _p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
    argv · 2012-04-01 19:45:17 0
  • this requires the use of a throwaway file. it outputs a shell function. assuming the throwaway file is f.tmp usage: >f.tmp;lso f.tmp > f.tmp; . f.tmp;rm f.tmp;lso -l ... notes: credit epons.org for the idea. however his version did not account for the sticky bit and other special cases. many of the 4096 permutations of file permissions make no practical sense. but chmod will still create them. one can achieve the same sort of octal output with stat(1), if that utility is available. here's another version to account for systems with seq(1) instead of jot(1): lso(){ case $# in 1) { case $(uname) in FreeBSD) jot -w '%04d' 7778 0000 7777 ;; *) seq -w 0000 7777 ;; esac; } \ |sed ' /[89]/d s,.*,printf '"'"'& '"'"';chmod & '"$1"';ls -l '"$1"'|sed s/-/./,' \ |sh \ |{ echo "lso(){"; echo "ls \[email protected] \\"; echo " |sed '"; sed ' s, ,@,2; s,@.*,,; s,\(.* \)\(.*\),s/\2/\1/,; s, ,,'; echo \'; echo }; }; ;; *) echo "usage: lso tmp-file"; ;; esac; } this won't print out types[1]. but its purpose is not to examine types. its focus is on mode and its purpose is to make mode easier to read (assuming one finds octal easier to read). 1. one could of course argue "everything is a file", but not always a "regular" one. e.g., a "directory" is really just a file comprising a list.


    0
    lso(){ jot -w '%04d' 7778 0000 7777 |sed '/[89]/d;s,.*,printf '"'"'& '"'"';chmod & '"$1"';ls -l '"$1"'|sed s/-/./,' \ |sh \ |{ echo "lso(){";echo "ls \[email protected] \\";echo " |sed '";sed 's, ,@,2;s,@.*,,;s,\(.* \)\(.*\),s/\2/\1/,;s, ,,';echo \';echo };};}
    argv · 2012-01-08 05:48:24 0
  • alternative to tr char '\012' works with sed's that don't accept "\n" allows for multi-char sentinals, while tr(1) only operates on single chars


    -4
    case $# in 0) echo usage: $0 pattern ;; *)case $1 in */*)sed ' s,'"$1"',\ ,g';; *) sed ' s/'"$1"'/\ /g' ;;esac;esac;
    argv · 2011-12-30 23:54:12 0
  • for small output only example usage: jobs -l |col1 72


    -3
    col1(){ case $# in 0)echo col1 col-length;;*) sed 's/\(.\{'"$1"'\}\)\(.*\)/\1/' esac;}
    argv · 2011-12-30 23:35:29 0

  • -3
    tmpfs(){ cd /;for i in [email protected];do tar czvf /tmp/$i $i;mount -t tmpfs tmpfs /$i;tar xvzf /tmp/$i;cd ~ ;}# usage: tmpfs etc var
    argv · 2011-12-30 23:27:56 0
  • _ff(){ cd /mnt; echo /mnt/*/* |sed ' s/ \/mnt\//\&/g; '|sed '/'"$1"'/!d'; cd -; } ff(){ case $# in 0) echo "usage: ff glob [sed-cmds] [--|var-name]" ;; 1) _ff $1 |sed = ;; [2-9]) case $2 in --) _ff $1 |less -SN ;; *) _ff $1 |sed -n ''"$2"''|tr '\n' '\040' |sed 's/.*/export '"$3"'=\"&/;s/=\" /=\"/;s/ $/\"/' > $HOME/.ff; case $# in 3) . $HOME/.ff ;; esac; sed ' s/export .*=\"/\$'"$3"' = \"/;' $HOME/.ff;\ ;; esac ;; esac; } v(){ local a=$HOME; sed ' s/export /less -n \$/; s/=.*//; ' $a/.ff > $a/.v ; . $a/.v ; } Another approach using ls(1) lsl(){ _lsl () { ls -l $3 /mnt/*/$1* 2>/dev/null; }; case $# in 0) echo "usage: lsl pat [ls-options|result-no]"; echo "usage: lsle pat [sed-cmds]" ;; 1) _lsl $1 |sed = ;; 2) case $2 in -*) _lsl $1 [email protected];; *) _lsl $1 |sed 's/.* //; '"$2"'!d; '"$2"'q' > $HOME/.lsl ; export v=$(sed 1q $HOME/.lsl); echo \$v = $v ;; esac ;; esac; } exp(){ echo "%s/\$/ /"; echo "%j"; echo "s/^/export v=\""; echo "s/\$/\""; echo "s/ \"\$/\""; echo "."; echo "wq"; } lsle(){ lsl $1 -1 |sed $2 > .lsl&& exp |ed -s .lsl >&-&& . .lsl&& echo \$v = $v; }


    -5
    _ff(){ cd /mnt;echo /mnt/*/* |sed 's/ \/mnt\//\&/g' |sed '/'"$1"'/!d'; cd -;}
    argv · 2011-12-30 23:25:31 2
  • does the -i option open a tmp file? this method does not.


    3
    sedi(){ case $# in [01]|[3-9])echo usage: sedi sed-cmds file ;;2)sed -a ''"$1"';H;$!d;g;' $2 |sed -a '/^$/d;w '"$2"'' ;;esac;}
    argv · 2011-07-27 02:36:53 0
  • usage: mem memcache-command [arguments] where memcache-command might be: set add get[s] append prepend replace delete incr decr cas stats verbosity version notes: exptime argument is set to 0 (no expire) flags argument is set to 1 (arbitrary)


    5
    mem(){ { case $1 in st*|[vgid]*) printf "%s " "[email protected]";; *) dd if=$3 2>&1|sed '$!d;/^0/d;s/ .*//;s/^/'"$1"' '"$2"' 1 0 /; r '"$3"'' 2>/dev/null;;esac;printf "\r\nquit\r\n";}|nc -n 127.0.0.1 11211; }
    argv · 2011-06-17 06:39:07 2
  • POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.


    1
    se(){ while read a;do [ "$a" != "${a#*[email protected]*}" ]&&echo $a;done ;} # usage: se pattern # use in place of sed /pat/!d where RE are overkill
    argv · 2011-04-06 03:37:40 2
  • this leaves the cursor at the bottom of the terminal screen, where your eyes are. ctrl-l moves it to the top, forcing you to look up.


    13
    cls(){ printf "\33[2J";} or, if no printf, cat >cls;<ctrl-v><ctrl+[>[2J<enter><ctrl+d> cls(){ cat cls;}
    argv · 2011-04-06 01:51:45 12
  • Sometimes the question comes up: How to get unbuffered tcpdump output into the next program in the pipe? i.e. if your OS forces you to wait for the buffer to fill before the next program sees any of the output If you use -Uw- then you can't use -A (or -X or -XX) at the same time. When the question comes up, I've never seen anyone suggest this simple solution: chaining 2 tcpdump instances.


    1
    tcp(){ tcpdump -nUs0 -w- -iinterface $1|tcpdump -n${2-A}r- ;} usage: tcp '[primitives]' [X|XX]
    argv · 2011-03-07 03:40:11 1
  • some other options: &delay=1000 &mode=links much more with piggybank as scraper works well with your favourite curses or non-curses http clients


    -1
    svn co http://simile.mit.edu/repository/crowbar/trunk&& cd ./trunk/xulapp/ xulrunner --install-app && Xvfb :1 && DISPLAY=:1 xulrunner application.ini 2>/dev/null 1>/dev/null && wget -O- "127.0.0.1:10000/&url=http://www.facebook.com"
    argv · 2010-10-16 05:12:11 0
  • Default output-file is "liveh.txt". This uses only BRE, in case you're using an older version of sed(1) that doesn't have support for ERE added. With a modern sed(1), to reduce false positive matches, you might do something like: liveh(){ tcpdump -lnnAs512 -i ${1-} tcp |sed 's/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/GET |Host: |POST /!d;/[\"'"'"]/d;/\.\./d;w '"${2-liveh.txt}"'' >/dev/null ;} Anyway, it's easy to clean up the output file with sed(1) later.


    5
    liveh(){ tcpdump -lnAs512 ${1-} tcp |sed ' s/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/[GPH][EOo][TSs]/!d;w '"${2-liveh.txt}"' ' >/dev/null ;} # usage: liveh [-i interface] [output-file] && firefox &
    argv · 2010-10-11 01:01:11 0
  • usage examples ls largedir |rd lynx -dump largewebsite.com |rd rd < largelogfile


    2
    rd(){ while read a ;do printf "$a\n";sleep ${1-1};done ;} # usage: rd < file ; or ... | rd
    argv · 2010-10-03 04:16:03 0
  • if you use disk-based swap then it can defeat the purpose of this function.


    4
    ram() { for i in /tmp /altroot;do mount -t tmpfs tmpfs $i;done&& for i in /var /root /etc $HOME; do find -d $i |cpio -pdmv /tmp&& mount -t tmpfs tmpfs $i&& mv -v /tmp$i/* $i&& rm -vrf /tmp$i ; done ;} usage: (in rc sequence) ram
    argv · 2010-08-31 08:25:55 0
  • EXAMPLES jb "next sun 12pm" "/bin/sh ~you/1.sh" & jb "2010-08-29 12:00:00" "~you/1.sh" & jb "29aug2010 gmt" ". ~you/1.sh" & jb 12:00p.m. "nohup ./1.sh" & jb 1min "echo stop!" & SEE ALSO parsedate(3) strftime(3)


    2
    jb() { if [ -z $1 ];then printf 'usage:\njb <"date and/or time"> <"commandline"> &\nsee parsedate(3) strftime(3)\n';else t1=$(date +%s); t2=$(date -d "$1" +%s) ;sleep $(expr $t2 - $t1);$2 ;fi ;}
    argv · 2010-08-26 23:50:42 0

  • 5
    st() { LDFLAGS=-static CFLAGS=-static CXXFLAGS=-static NOSHARED=yes ./configure [email protected] ;} usage: st [configure operands]
    argv · 2010-08-20 08:18:56 0

  • 7
    cls(){ printf "\033c";} or, if no printf, cat > c ;<ctrl+v> <ctrl+[>c <enter><ctrl-d> c(){ cat c;} #usage: c
    argv · 2010-08-02 07:27:22 1

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Stream YouTube URL directly to mplayer.
This is the result of a several week venture without X. I found myself totally happy without X (and by extension without flash) and was able to do just about anything but watch YouTube videos... so this a the solution I came up with for that. I am sure this can be done better but this does indeed work... and tends to work far better than YouTube's ghetto proprietary flash player ;-) Replace $i with any YouTube ID you want and this will scrape the site for the _real_ URL to the full quality .FLV file on Youtube's server and will then will hand that over to mplayer (or vlc or whatever you want) to be streamed. In some browsers you can replace $i with just a % or put this in a shell script so all YouTube IDs can be handed directly off to your media player of choice for true streaming without the need for Flash or a downloader like clive. (I do however fully recommend clive if you wish to archive videos instead of streaming them) If any interest is shown I would be more than happy to provide similar commands for other sites. Most streaming flash players use similar logic to YouTube. Edit: 05/03/2011 - Updated line to work with current YouTube. It could be a lot prettier but I will probably follow up with another update when I figure out how to get rid of that pesky Grep. Sed should take that syntax... but it doesn't. Original (no longer working) command: mplayer -fs $(echo "http://youtube.com/get_video.php?$(curl -s $youtube_url | sed -n "/watch_fullscreen/s;.*\(video_id.\+\)&title.*;\1;p")")

Get video information with ffmpeg
I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.

A simple way to securely use passwords on the command line or in scripts
In this example, where the users gpg keyring has a password, the user will be interactively prompted for the keyring password. If the keyring has no password, same as above, sans the prompt. Suitable for cron jobs. ~/.gnupg/passwd/http-auth.gpg is the encrypted http auth password, for this particular wget use case. This approach has many use cases. example bash functions: function http_auth_pass() { gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null; } function decrypt_pass() { gpg2 --decrypt ~/.gnupg/passwd/"$1" 2>/dev/null; }

Install a new kernel in Manjaro linux
00 is the number of the linux kernel e.g. linux39

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Tracklist reaplace backspace to '-'
Requires perl 5.14 or greater

Archive a directory with datestamp on filename
A useful bash function: gztardir() { if [ $# -ne 1 ] ; then echo "incorrect arguments: should be gztardir " else tar zcvf "${1%/}-$(date +%Y%m%d-%H%M).tar.gz" "$1" fi }

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Sync MySQL Servers via secure SSH-tunnel
I wanted to keep a backup of my company database server on my local homeserver. After I found maatkit to sync databases, everything except security seemed fine. SSH takes care of that part.

Find Duplicate Files (based on MD5 hash) -- For Mac OS X
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.


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