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Commands using tail from sorted by
Terminal - Commands using tail - 224 results
open-command $(ls -rt *.type | tail -n 1)
2010-04-04 20:43:38
User: RBerenguel
Functions: ls tail
0

Change open-command and type to suit your needs. One example would be to open the last .jpg file with Eye Of Gnome:

eog $(ls -rt *.jpg | tail -n 1)

curl -s -L --head -w "%{http_code}\n" URL | tail -n1
TR=`free|grep Mem:|awk '{print $2}'`;ps axo rss,comm,pid|awk -v tr=$TR '{proc_list[$2]+=$1;} END {for (proc in proc_list) {proc_pct=(proc_list[proc]/tr)*100; printf("%d\t%-16s\t%0.2f%\n",proc_list[proc],proc,proc_pct);}}'|sort -n |tail -n 10
2010-03-27 01:34:50
User: d34dh0r53
Functions: awk grep sort tail
3

Prints the top 10 memory consuming processes (with children and instances aggregated) sorted by total RSS and calculates the percentage of total RAM each uses. Please note that since RSS can include shared libraries it is possible for the percentages to add up to more that the total amount of RAM, but this still gives you a pretty good idea. Also note that this does not work with the mawk version of awk, but it works fine with GNU Awk which is on most Linux systems. It also does not work on OS X.

find * \( -name "*.[hc]pp" -or -name "*.py" -or -name "*.i" \) -print0 | xargs -0 wc -l | tail -n 1
2010-03-25 18:58:29
User: neologism
Functions: find tail wc xargs
Tags: find xargs wc
1

Finds all C++, Python, SWIG files in your present directory (uses "*" rather than "." to exclude invisibles) and counts how many lines are in them. Returns only the last line (the total).

ps axo rss,comm,pid | awk '{ proc_list[$2] += $1; } END { for (proc in proc_list) { printf("%d\t%s\n", proc_list[proc],proc); }}' | sort -n | tail -n 10
ps axo rss,comm,pid | awk '{ proc_list[$2]++; proc_list[$2 "," 1] += $1; } END { for (proc in proc_list) { printf("%d\t%s\n", proc_list[proc "," 1],proc); }}' | sort -n | tail -n 10
2010-03-03 16:41:05
User: d34dh0r53
Functions: awk ps sort tail
5

This command loops over all of the processes in a system and creates an associative array in awk with the process name as the key and the sum of the RSS as the value. The associative array has the effect of summing a parent process and all of it's children. It then prints the top ten processes sorted by size.

TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"
2010-02-26 20:29:45
User: d34dh0r53
Functions: awk echo grep head tail
6

Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

tail -n 50 -f /var/log/apache2/access_log /var/log/apache2/error_log
2010-02-21 14:45:44
User: warlock
Functions: tail
5

-f file(s) to be monitorized

-n number of last line to be printed on the screen

in this example, the content of two files are displayed

find /path/to/dir -type f -printf "%T@|%p\n" 2>/dev/null | sort -n | tail -n 1| awk -F\| '{print $2}'
tail -f /var/log/apache2/access.log | awk -W interactive '!x[$1]++ {print $1}'
2010-01-12 15:23:03
User: pykler
Functions: awk tail
1

Prints the unique IP Addresses as they arrive from an Apache `access.log` file.

The '-W interactive' tells awk to start writing to stdout immediately and not buffer the output.

This command builds on the uniq lines without sorting command (http://www.commandlinefu.com/commands/view/4389/remove-duplicate-entries-in-a-file-without-sorting.)

find /home/bubo/ -type f \( -iname \*.jpg -print0 , -iname \*.png -print0 , -iname \*gif -print0 \) | du -cm --files0-from - | tail -1
watch 'dmesg | tail -15'
2009-12-20 02:00:05
User: Heoa
Functions: tail watch
-1

Useful with new unknown devices or just monitoring, probably useful for the sysadmin. Updates every 2 seconds. More here: http://linuxclisecurity.blogspot.com/2009/12/monitor-kernel-ring-buffer.html.

zcat access_log.*.gz | awk '{print $7}' | sort | uniq -c | sort -n | tail -n 20
tail $0 >> $0
2009-12-07 12:33:41
User: yooreck
Functions: tail
Tags: dd df
1

Put into some file. No special purpouse, just for fun...

git diff --stat `git log --author="XXXXX" --since="12 hours ago" --pretty=oneline | tail -n1 | cut -c1-40` HEAD
2009-11-04 01:41:33
User: askedrelic
Functions: cut diff tail
3

Figures out what has changed in the last 12 hours.

Change the author to yourself, change the time since to whatever you want.

echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" | nc whatismyip.com 80 | tail -n1
ps -eo user,pcpu,pmem | tail -n +2 | awk '{num[$1]++; cpu[$1] += $2; mem[$1] += $3} END{printf("NPROC\tUSER\tCPU\tMEM\n"); for (user in cpu) printf("%d\t%s\t%.2f\t%.2f\n",num[user], user, cpu[user], mem[user]) }'
2009-10-29 12:49:01
User: georgz
Functions: awk ps tail
7

The original version gives an error, here is the correct output

tail -F file | egrep --color 'pattern|$'
tail -f file | egrep --color=always $\|PATTERN
2009-10-15 13:08:30
User: sitaram
Functions: egrep file tail
Tags: color
-2

but you can't see the colors in that sample output :(

tail -f FILE | grep --color=always KEYWORD
dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
2009-10-12 14:57:54
User: pykler
Functions: bash cut du echo read sed tail tr xargs
Tags: Debian wajig
4

Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the

| sort -rn

which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side

Also you may need to run this as root as some files can only be checked by du if you can read them ;)

wget -q -O - 'http://wap.weather.gov.hk/' | sed -r 's/<[^>]+>//g;/^UV/q' | tail -n4
2009-09-25 02:36:46
User: dakunesu
Functions: sed tail wget
-1

"get Hong Kong weather infomation from HK Observatory

From Hong Kong Observatory wap site ;)"

other one showed alot of blank lines for me

find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($t +=$1) && printf "%02d:%02d:%02d\n",$t/3600,$t/60%60,$t%60' | tail -n 1
2009-09-24 15:50:39
User: syssyphus
Functions: find perl printf tail xargs
8

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

lsof -P -i -n | cut -f 1 -d " "| uniq | tail -n +2
ls -t | tail +6 | xargs rm