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 9
  • 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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Makes the permissions of file2 the same as file1
Also works with: $chgrp --reference file1 file2 $chown --reference file1 file2

make, or run a script, everytime a file in a directory is modified

most changed files in domains by rdiff-backup output

Create a backup of the file.
It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.

dd with progress bar and statistics to gzipped image
This is a useful command to backup an sd card with relative total size for piping to pv with a progressbar

Processes by CPU usage

read squid logs with human-readable timestamp

For finding out if something is listening on a port and if so what the daemon is.

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Create cheap and easy index.html file
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file.


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