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Commands by postrational

Commands by postrational from sorted by
Terminal - Commands by postrational - 5 results
sort -t $'\t' -k 2 input.txt
2010-07-11 12:58:51
User: postrational
Functions: sort
Tags: Text Processing sort cut bash tricks join
4
Up
Down
Pass TAB as field separator to sort, join, cut, etc.

Use this BASH trick to create a variable containing the TAB character and pass it as the argument to sort, join, cut and other commands which don't understand the \t notation.

sort -t $'\t' ... join -t $'\t' ... cut -d $'\t' ...
Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cut -f 1 three-column.txt > first-column.txt
2010-07-11 10:13:45
User: postrational
Functions: cut
Tags: Text Processing bash extract oneliner while substitution
4
Up
Down
Short one line while loop that outputs parameterized content from one file to another

There is a common command for outputting a field or list of fields from each line in a file. Why wouldn't you just use cut?

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dig -x 74.125.45.100
2009-09-28 15:13:34
User: postrational
Functions: dig
Tags: dig host reverse dns nslookup
3
Up
Down
Perform a reverse DNS lookup

Performs a reverse DNS lookup, variants include:

nslookup 74.125.45.100

or:

host 74.125.45.100
Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
export HISTTIMEFORMAT='%F %T '
2009-09-26 17:13:23
User: postrational
Functions: export
6
Up
Down
save date and time for each command in history

Date-time format: YYYY-MM-DD HH:MM:SS

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | sed -n "s/<title>\(.*\)<\/title.*name>\(.*\)<\/name>.*/\2 - \1/p"
2009-09-07 21:56:40
User: postrational
Functions: awk sed tr
Tags: Linux perl sed awk macosx curl rss gmail
41
Up
Down
Check your unread Gmail from the command line

Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages.

For some reason sed gets stuck on OS X, so here's a Perl version for the Mac:

curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*<name>(.*)<\/name>.*$/$2 - $1/'

If you want to see the name of the last person, who added a message to the conversation, change the greediness of the operators like this:

curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*?<name>(.*?)<\/name>.*$/$2 - $1/'
Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate