Delete last N lines from bash history
When accidentally pasting a file into the shell it puts a ton of ugly nonsense entries in the bash history. Is there a clean way to remove those entries? Obviously I could close the shell and edit the .bash_history file manually but maybe there’s some kind of API available to modify the history of the current shell?
14 Answers 14
Just this one liner in command prompt will help.
for i in ; do history -d START_NUM; done Where START_NUM is starting position of entry in history. N is the number of entries you may want to delete.
ex: for i in ; do history -d 1030; done
askubuntu.com/a/978276/22866 has a nice way to delete the «delete from history command» from history 🙂
@RajeevAkotkar If the delete command is the nth line, then using N+1 in the for loop will also help delete the command that did the deleting.
Alternatively, you can also use for i in <1030..1080>; do history -d 1030; done instead — which might be a bit more intuitive. I wrote a small bash script, just replace 1030 with $1 and 1080 with $2 .
As of bash-5.0-alpha , the history command now takes a range for the delete ( -d ) option. See rastafile’s answer.
For older versions, workaround below.
You can use history -d offset builtin to delete a specific line from the current shell’s history, or history -c to clear the whole history.
It’s not really practical if you want to remove a range of lines, since it only takes one offset as an argument, but you could wrap it in a function with a loop.
Call it with rmhist first_line_to_delete last_line_to_delete . (Line numbers according to the output of history .)
(Use history -w to force a write to the history file.)
Since the OP asked for deleting the N last lines, this script should be modified by doing something like: tot_lines=$(history | wc -l) and then repeat history -d $(( tot_lines — $1 )) .
The history bash built-in command also takes a range, now in 2020:
-d offset
Delete the history entry at position offset. If offset is negative, it is interpreted as relative to one greater than the last history position, so negative indices count back from the end of the history, and an index of -1 refers to the current history -d command.
-d start-end
Delete the history entries between positions start and end, inclusive. Positive and negative values for start and end are interpreted as described above.
Only the command itself does not tell with —help :
Options: -c clear the history list by deleting all of the entries -d offset delete the history entry at position OFFSET. Negative offsets count back from the end of the history list -a append history lines from this session to the history file . E.g. history -d 2031-2034 deletes four lines at once. You could use $HISTCMD to delete from the newest N lines backwards.
You can also export with history -w tmpfile , then edit that file, clear with history -c and then read back with history -r tmpfile . No write to .bash_history.
If you delete line N from the history, then line N+1 moves in position N etc.
For this reason, I prefer identifying the oldest and newest history line between which I want to delete all history. (Note: oldest < newest ).
If for instance I want to delete the history lines from oldest = 123 up to newest = 135 , I’d write:
$ for i in ; do history -d $i ; done I find it easier to read; besides: the for command can also decrement a range.
the history -d arg takes a range and $HISTCMD is the max number in the history.
This function works to remove the last n entries from history (just pass in the number of history commands to remove like, eg rmhist 5 :
Or.. Go fancy with an arg like this to remove from a point in history (inclusive) or last ‘n’ commands:
The result looks something like this:
5778 ls /etc 5779 ls /tmp 5780 ls /dev 5781 ll 5782 cd /tmp 5783 cd 5784 history (base) ~ $ rmhist --last 3 (base) ~ $ history 5 5778 ls /etc 5779 ls /tmp 5780 ls /dev 5781 ll 5782 history 5 (base) ~ $ rmhist --from 5780 (base) ~ $ history 5 5776 history 10 5777 ls 5778 ls /etc 5779 ls /tmp 5780 history 5 I get «bash: history: N: history position out of range» errors, but this worked for me to delete the last entry hdl() < history -d $(($HISTCMD - $1))-$(($HISTCMD - 2)) ;>I’ll write any error understandings in my answer here: unix.stackexchange.com/a/573258/346155
What’s different in this answer: it also displays what is being deleted.
For those using Bash 4.x (e.g. in Centos 7 and lower), I use this to delete the last N items in the history including the command to do this. (here N=5)
for i in ; do echo "clearing line $(($HISTCMD-2)): $(history -p \!$(($HISTCMD-2)))"; history -d $(($HISTCMD-2)); done; history -d $(($HISTCMD-1)) To delete the history lines between n and m (e.g. here 544 and 541), I use the following. NOTE: you must enter the bigger line number first and then the smaller one:
for i in ; do echo "clearing line $i: $(history -p \!$i)"; history -d $i; done; history -d $(($HISTCMD-1)) The answer by user2982704 almost worked for me but not quite. I had to make a small variation like this.
Assuming my history is is at 1000 and I want to delete the last 50 entries
start=1000 for i in ; do count=$((start-i)); history -d $count; done It works for me. To delete line 2 to 29 (includes line 2 and line 29):
This should delete every history list entry in reverse order N times:
If you want to add this to your .bashrc, use:
..and then source ~/.bashrc to reload bash config. Use as:
hd , where N is the number of lines to delete My other answer for a different approach that is not working, but is long and complicated.
EDIT: this started giving me the error «bash: history: -N: history position out of range» as does history -d -2 for some reason. So I used another users answer, that even though it gave me the same error, I could adjust to make work. This example deletes only the last line, but can be extended.
Before I give up on this alternative approach, I want to put down what I’ve learned. Part of my difficulty in debugging my first answer is that its a bit unclear how many N ends up being, because it includes the current command, so I think it is really N-1 or maybe N-2.
To make it more clear, I was trying a solution that would delete from a line number going forward. And wow, what a big surprise of how difficult that is. The main problem is the history routine is running in the background so deleting say number 50 will result in number 51 now being 50 in less than a second. So I tried making a function to delete going backwards from the end. And when trying to deleting 10 in a row and it gets about 5 before running out of commands as they shift down. So I tried making a function to delete forwards and it, for some reason only gets every other one. Consistent with the history routine running about half as fast as the function. I also tried inserting sleep at certain points.
I tried turning off history temporarily, but then $HISTCMD show the total from $HISTFILE not the history list. So it looks nary a possible. My goal was to clean the history of unnecessary commands so that I could memorize the bang number !# and use the same ones going forward for frequent and difficult commands.
Here’s some of the functions I tried. Maybe someone can improve or diagnose:
Going from the Number to the end: function hd2 < a=$HISTCMD; echo $a; echo $1; echo $(($a%$1)); for i in $(seq $1 $a); do echo $i; history -d $i; done; >Deleting from the end repeatedly with sleep: function hd3 < a=$HISTCMD; echo $a; echo $1; echo $(($a%$1)); for i in $(seq 1 $a); do history -d $HISTCMD; sleep 1; done; >Deleting the Number repeatedly with sleep: function hd4
The beginning echo variable are for debugging. % is remainder or mod. $HISTCMD does not carry through command substitution and need to be assigned as a variable.
new idea: since the function below works with repeated use:
echo "function hdn < history -d \$1; >">>~/.bashrc echo "function hdn2 < for i in $(seq 1 \$2); history -d \$1; sleep 1; done; >">>~/.bashrc how do I remove the last 5 lines in bash history?
How can I remove the last 5 lines in bash history? So that when I reload the Ubuntu server, or restart it they’re not there at all? history -c only removes it from current session, but when I re-login I see the commands again, I want to clear the last 5. I’ve run:
489 cd .. 490 cd .zshrc 491 cat .zshrc Then i close terminal and reopen it and i still see line 489 it was only deleted for that current session, how do I delete it permentantly from all sessions going forward?
Is the history file not just a simple .txt file that can be edited?. Sorry in Windows right now and never actually tried.
5 Answers 5
You can achieve removal from the history file using the command line in two steps:
Typing history -d deletes a specified line from the history in memory. Typing history -w writes the current in-memory history to the ~/.bash_history file. The two steps together remove the line permanently from the in-memory history and from the .bash_history file as well.
This is a lot closer, so I run history -wd 493 for example, and it works to delete it for good, however, then in history I have a bunch of history -wd’s etc. so it’s counterintuitive, how can i clear e.g. the last 5 commands all in one shot that would be best, and then the actual command i used to clear them itself.
@EODCraftStaff Type man and the name of the command manual you want to see. In this case: man history .
Use a space before your history delete command and it wont go to your history after it removes content from the history. Alternately, kill -s 9 $$ when you’re done.
I think you need to try this its very easy & simple.
- How to delete history without any trace
history -d $((HISTCMD-1)) && history -d NO_of_History_you_want_to_delete history -d $((HISTCMD-1)) && type_your_command_here_and_execute (2.) doesn’t answer the question and it would be far easier to prepend the traceless command with a space character to omit its addition to the history.
(1.) is both an excellent and elegant solution. I’m not sure how adding a space prevents it from being added to the history, David
@theking2 For some systems pre-pending a space tells bash not to write the command to the history https://stackoverflow.com/questions/6475524.
There are different ways to accomplish this task, but lets clarify something before going further.
There is a file named: ~/.bash_history , which contains your older terminal sessions history, whenever you close your terminal, your history will be saved there.
At the same time the history of your old sessions along with current session is temporary accessible by history commands until you close the terminal which then will be saved into ~/.bash_history file.
So if you remove 5 lines at the end of ~/.bash_history , then closing terminal will cause your current command to be accessible at next sessions.
So if I do a wc on .bash_history:
Most of the time I’ll get a smaller number than of history | wc -l .
If you want to remove the last 5 line of the file, you can use this command:
for i in ; do sed -i '$d' .bash_history; done; And if you want to keep all history except last 5 command issued in current session run:
history | awk '< print $2 >' | head -n -5 > .bash_history Don’t forget to run history -c too.