History list without timestamp and unique the results

Question

Using bash, I save my history with the timestamp.

How do print the history omitting the timestamp?

alias h=history
alias g=grep -i

To find lines that I used for heroku, I type:

> h | g heroku

I'd like to unique the results without the time-stamp, naturally.

This question is somewhat related: How to avoid duplicate entries in .bash_history

However, sometimes I want to see the duplicate in the history to see the context under which a command was run.

Answer 1

Simply, history | sed 's/.[ ]*.[0-9]*.[ ]*//' | uniq | grep -i "heroku"

the sed will remove the any [spaces][numbers][spaces] at the start of each line

for optimization make it

history | grep -i "heroku" | sed 's/.[ ]*.[0-9]*.[ ]*//' | uniq

Answer 2

Addition to answer by @devav2

Clear/nullify the history timestamp environment variable

HISTTIMEFORMAT="";

Export the following command,

export HISTCONTROL=ignoredups --> This will ignore the duplicates that are executed in sequence

Answer 3

The timestamp can be suppressed (or modified) on a per-command basis:

If the HISTTIMEFORMAT variable is set and not null, its value is used as a format string for strftime(3) to print the time stamp associated with each displayed history entry. No time stamps are printed otherwise.

That just leaves the line numbers, which can't be suppressed, but which are padded to a fixed width (for line numbers < 100,000):

printf("%5d%c %s%s\n", line_number, modified ? '*' : ' ', timestamp, line);

Thus, to remove the prefix from each line, we need to snip the first 7 characters (5 digits, 1 marker character, and 1 space) e.g.:

$ HISTTIMEFORMAT= history 10 | cut -c8-

This can easily be added to an alias:

$ alias h='HISTTIMEFORMAT= history | cut -c8-'

Then invoked with e.g.:

$ h | grep whatever
$ h | head -n 10

Answer 4

Show unique lines of the command history sorted.

history | sed 's/.[ ]*.[0-9]*.[ ]*//' | sort -u

then add a keyword grep to find a specific keyword,

history | sed 's/.[ ]*.[0-9]*.[ ]*//' | sort -u | grep -w "keyword"

such as this -- if you are looking, say, for all of your unique "ls" commands.

history | sed 's/.[ ]*.[0-9]*.[ ]*//' | sort -u | grep -w "ls"

Answer 5

You can also temporarily disable timestamps

HISTTIMEFORMAT="" history

To just list the actual commands, do

HISTTIMEFORMAT="" history | sed 's@ *[0-9]* *@@'

You can make this a function

history-raw() { HISTTIMEFORMAT="" history | sed 's@ *[0-9]* *@@'; }

Answer 6

use simpel:

history | cut -b 28-