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 \$@ \\"; 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 \$@ \\";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 $@;do tar czvf /tmp/$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 $@;; *) _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 $1 in st*|[vgid]*) printf "%s " "$@";; *) 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#*$@*}" ]&&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 0
  • 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 $@ ;} 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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wrap long lines of a text
wraps text lines at the specified width (90 here). -s option is to force to wrap on blank characters -b count bytes instead of columns

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

USE WITH CAUTION: perminately delete old kernel packages

Create a file of a given size in linux

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"

Printable random characters
Reads psuedorandom bytes from /dev/urandom, filtering out non-printable ones. Other character classes can be used, such as [:alpha:], [:digit:] and [:alnum:]. To get a string of 10 lowercase letters: $ tr -dc '[:lower:]' < /dev/urandom | head -c 10

Multiple variable assignments from command output in BASH
No command substitution but subshell redirection

quick and dirty formatting for HTML code
Finds all the closing tags in a HTML document via non-greedy regex and adds a linefeed for easier reading/editing . sed -i.bak -r 's_(/[^>]*?>)_\1\n_g' filename.html . This will save a copy of filename.html as filename.html.bak and then add the linefeeds to the original file

View the current number of free/used inodes in a file system
tune2fs also provides the same information . But the information does not give the current usage , it gives the information when the file system was last mounted. http://www.zaman4linux.in/2010/10/using-up-all-the-free-inodes.html

Recursively remove directory with many files quickly
rsync'ing an empty directory over a directory to be deleted recursively is much faster than using rm -rf, for various reasons. Relevant only for directories with really a lot of files.


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