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1 votes

4 answers

520 views

How do I print line numbers but reset line counter at empty line?

I have a file.txt containing: ``` this is the first second line not last line fourth but first second in list seventh in file seventh with nl ``` Normally I would just `cat` and pipe `|` it into `nl` like so: ```bash $> cat file.txt | nl 1 this is the first 2 second line 3 not last line 4 fourth but...

I have a file.txt containing:

this is the first
second line
not last line

fourth but first
second in list
seventh in file
seventh with nl

Normally I would just cat and pipe | it into nl like so:

$> cat file.txt | nl
1  this is the first
2  second line
3  not last line

4  fourth but first
5  second in list
6  seventh in file
7  seventh with nl

But I need the line numbers to reset when it encounters an empty line like so:

$> alias_or_function file.txt
1  this is the first
2  second line
3  not last line

1  fourth but first
2  second in list
3  seventh in file
4  seventh with nl

How could I do this using a quick function or alias in my ~/.zshrc?

ntruter42 (197 rep)

Aug 22, 2020, 04:17 AM • Last activity: Mar 3, 2025, 07:36 PM

9 votes

5 answers

1562 views

nl: How to start line numbers on the second line?

ls nl

This is the standard output of `ls -ln | nl` wolf@linux:~$ ls -lh | nl 1 total 24 2 -rw-rw-r-- 1 wolf wolf 186 Sep 24 22:18 01.py 3 -rw-rw-r-- 1 wolf wolf 585 Sep 24 22:21 02.py 4 -rw-rw-r-- 1 wolf wolf 933 Sep 24 22:26 03.py wolf@linux:~$ Instead of starting the number from `total 24`, would it be...

                                  This is the standard output of ls -ln | nl

    wolf@linux:~$ ls -lh | nl
         1	total 24
         2	-rw-rw-r-- 1 wolf wolf  186 Sep  24 22:18 01.py
         3	-rw-rw-r-- 1 wolf wolf  585 Sep  24 22:21 02.py
         4	-rw-rw-r-- 1 wolf wolf  933 Sep  24 22:26 03.py
    wolf@linux:~$

Instead of starting the number from total 24, would it be possible to start it from the actual files/directory which is the second line?

Desired output

    wolf@linux:~$ ls -lh | nl
         	total 24
         1	-rw-rw-r-- 1 wolf wolf  186 Sep  24 22:18 01.py
         2	-rw-rw-r-- 1 wolf wolf  585 Sep  24 22:21 02.py
         3	-rw-rw-r-- 1 wolf wolf  933 Sep  24 22:26 03.py
    wolf@linux:~$
                                

Wolf (1741 rep)

Sep 25, 2020, 11:29 AM • Last activity: Feb 11, 2025, 07:06 PM

1 votes

2 answers

469 views

head not returning n lines

linux command-line command head nl

When I run the command `head -n 445 /etc/snort/snort.conf | nl` I expect lines 1-445 to be returned. However, only up to line 371 is returned: [snip] 370 preprocessor dcerpc2_server: default, policy WinXP, \ 371 detect [smb [139, 445], tcp 35, udp 135, rpc-over-http-server 593], \ What is happening?

                                  When I run the command head -n 445 /etc/snort/snort.conf | nl I expect lines 1-445 to be returned. However, only up to line 371 is returned:

    [snip]
    370 preprocessor dcerpc2_server: default, policy WinXP, \
    371     detect [smb [139, 445], tcp 35, udp 135, rpc-over-http-server 593], \

What is happening?
                                

Syd (13 rep)

Nov 17, 2019, 05:20 PM • Last activity: Aug 19, 2023, 07:18 PM

1 votes

2 answers

957 views

nl without additional leading tab/space

text-processing nl

I notice that there is additional leading tab/space whenever `nl` is used. wolf@linux:~$ echo ABC ABC wolf@linux:~$ wolf@linux:~$ echo ABC | nl 1 ABC wolf@linux:~$ Is there any option to disable this? Desired Output wolf@linux:~$ echo ABC | nl 1 ABC wolf@linux:~$

                                  I notice that there is additional leading tab/space whenever nl is used.

    wolf@linux:~$ echo ABC
    ABC
    wolf@linux:~$ 
    
    wolf@linux:~$ echo ABC | nl
         1	ABC
    wolf@linux:~$ 

Is there any option to disable this?

Desired Output

    wolf@linux:~$ echo ABC | nl
    1	ABC
    wolf@linux:~$ 
                                

Wolf (1741 rep)

Nov 16, 2020, 12:55 PM • Last activity: Nov 16, 2020, 12:59 PM

-1 votes

1 answers

67 views

least astonishment transgressed by `nl` on Darwin

darwin nl

Transgression of [least astonishment][0]: ``` bash-5.0$ (for i in {1..1000010}; do echo $i; done) | nl | tail -24 999987 999987 999988 999988 999989 999989 999990 999990 999991 999991 999992 999992 999993 999993 999994 999994 999995 999995 999996 999996 999997 999997 999998 999998 999999 999999 0000...

Transgression of least astonishment :

bash-5.0$ (for i in {1..1000010}; do echo $i; done) | nl | tail -24
999987	999987
999988	999988
999989	999989
999990	999990
999991	999991
999992	999992
999993	999993
999994	999994
999995	999995
999996	999996
999997	999997
999998	999998
999999	999999
000000	1000000
000001	1000001
000002	1000002
000003	1000003
000004	1000004
000005	1000005
000006	1000006
000007	1000007
000008	1000008
000009	1000009
000010	1000010
bash-5.0$ uname -a
Darwin llc.local 19.4.0 Darwin Kernel Version 19.4.0: Wed Mar  4 22:28:40 PST 20
20; root:xnu-6153.101.6~15/RELEASE_X86_64 x86_64        
bash-5.0$ sw_vers 
ProductName:	Mac OS X
ProductVersion:	10.15.4
[...]
bash-5.0$ _

Compare with expectation:

admin@ip-w-x-y-z:~$ (for i in {1..1000010}; do echo $i; done) | nl | tail -24
999987	999987
999988	999988
999989	999989
999990	999990
999991	999991
999992	999992
999993	999993
999994	999994
999995	999995
999996	999996
999997	999997
999998	999998
999999	999999
1000000	1000000
1000001	1000001
1000002	1000002
1000003	1000003
1000004	1000004
1000005	1000005
1000006	1000006
1000007	1000007
1000008	1000008
1000009	1000009
1000010	1000010
admin@ip-w-x-y-z:~$ uname -a
Linux ip-w-x-y-z 4.9.0-9-amd64 #1 SMP Debian 4.9.168-1+deb9u4 (2019-07-19)
 x86_64 GNU/Linux
admin@ip-w-x-y-z:~$ lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux 9.9 (stretch)
Release:	9.9
Codename:	stretch
admin@ip-w-x-y-z:~$ _

I'm curious what are your thoughts about this and how to overcome. Thanks.

41754 (95 rep)

Apr 7, 2020, 07:54 AM • Last activity: Sep 23, 2020, 03:51 PM

1 votes

2 answers

388 views

`nl` invocation soaking all input before numbering

command-line logs console nl tracing

How can this be done? I don't see any applicable option in the manual. I have positively checked that indentation breaks after ten million lines. You can check it like: $ (for i in `seq 0 10000000`; do echo "$i"; done) | nl I don't often generate so many lines, but I don't want it to break like it d...

                                  How can this be done?

I don't see any applicable option in the manual.

I have positively checked that indentation breaks after ten million lines.

You can check it like:

    $ (for i in seq 0 10000000; do echo "$i"; done) | nl

I don't often generate so many lines, but I don't want it to break like it does. How can this be done?

41754 (95 rep)

Jan 14, 2015, 10:53 AM • Last activity: Sep 23, 2020, 03:51 PM

2 votes

3 answers

157 views

how to align hypen

grep text-formatting cut nl

This is my command ``` echo -e "Test sur la vie, l'univers et le reste \n " >test42 |grep '42' questions.txt | nl -w1 -s ' - ' | cut -d "/" -f 1 >> test42 ``` this is the output ``` Test sur la vie, l'univers et le reste 1 - Quel est le numéro de la dernière armure de Tony Stark dans le fi...

This is my command

echo -e  "Test sur la vie, l'univers et le reste \n " >test42 |grep '42' questions.txt | nl -w1  -s '  - ' | cut -d "/" -f 1 >> test42

this is the output

Test sur la vie, l'univers et le reste 
 
1  - Quel est le numéro de la dernière armure de Tony Stark dans le film Iron Man 3 ?
2  - Quel est l’angle visuel entre la partie colorée d’un arc-en-ciel et le point central de son arc ?
3  - Quel est le score maximal réalisable à titre individuel au cours des Olympiades internationales de mathématiques ?
4  - À combien de gallons un baril de pétrole est-il équivalent ?
5  - Quel est le nombre d’années de mariage des noces de nacre ?
6  - Quelle est la résistance mécanique en GPa du graphène ?
7  - Combien d'éclipses de soleil et de lune durant un saros ?
8  - Quel est le numéro de l’inode du répertoire root dans un système de fichier reiser4 ?
9  - Combien la Bible de Gutenberg comporte de lignes de texte par colonne ?
10  - Quel est le titre de l'épisode 3X07 de la série télévisée Doctor Who ?
11  - Quel est le numéro atomique du molybdène, un métal de transition ?

But the result should be like this

Test sur la vie, l'univers et le reste

1  - Quel est le numéro de la dernière armure de Tony Stark dans le film Iron Man 3 ?
2  - Quel est l’angle visuel entre la partie colorée d’un arc-en-ciel et le point central de son arc ?
3  - Quel est le score maximal réalisable à titre individuel au cours des Olympiades internationales de mathématiques ?
4  - À combien de gallons un baril de pétrole est-il équivalent ?
5  - Quel est le nombre d’années de mariage des noces de nacre ?
6  - Quelle est la résistance mécanique en GPa du graphène ?
7  - Combien d'éclipses de soleil et de lune durant un saros ?
8  - Quel est le numéro de l’inode du répertoire root dans un système de fichier reiser4 ?
9  - Combien la Bible de Gutenberg comporte de lignes de texte par colonne ?
10 - Quel est le titre de l'épisode 3X07 de la série télévisée Doctor Who ?
11 - Quel est le numéro atomique du molybdène, un métal de transition ?
12 - Quelle est la taille, en mètre, de l'obélisque inachevé dans la carrière d'Assouan en Égypte ?

I need to have 2 spaces between the number 1 to 9 and the hypen. But i need to have only 1 space between the hypen and number 10 and more. Do you guys have any idea ? Thanks

david b.k (39 rep)

Feb 19, 2020, 09:48 PM • Last activity: Feb 19, 2020, 11:26 PM

2 votes

3 answers

6884 views

Line Number for all non-blank lines?

text-processing cat nl

Kind of amused here, I'm trying to pass the [prereqs](https://classroom.udacity.com/courses/ud219/lessons/972928869/concepts/9977987120923) to get into the [Udacity Course on High Performance Computer Architecture by Georgia Institute of Technology](https://www.udacity.com/course/high-performance-co...

                                  Kind of amused here, I'm trying to pass the [prereqs](https://classroom.udacity.com/courses/ud219/lessons/972928869/concepts/9977987120923)  to get into the [Udacity Course on High Performance Computer Architecture by  Georgia Institute of Technology](https://www.udacity.com/course/high-performance-computer-architecture--ud007)  For the life of me I can't figure out what they want,

Question reads,

> To list the contents of a file, with line numbers for non-blank line shown use the command with an option: ________ ___ filename.

I've tried nl. It didn't work. Most bizarre question ever.

Evan Carroll (34663 rep)

Apr 17, 2018, 11:11 PM • Last activity: Feb 8, 2020, 05:10 PM

1 votes

1 answers

335 views

What is considered a header and footer in a text formatted for printing?

text-processing nl

From `nl` manual: ... -f, --footer-numbering=STYLE use STYLE for numbering footer lines -h, --header-numbering=STYLE use STYLE for numbering header lines ... Can you provide an example of usage of the `-f` and `-h` option? What is considered as being a footer or header?

                                  From nl manual:

    ...

    -f, --footer-numbering=STYLE
              use STYLE for numbering footer lines

    -h, --header-numbering=STYLE
           use STYLE for numbering header lines

    ...

Can you provide an example of usage of the -f and -h option? What is considered as being a footer or header?

user123456 (5258 rep)

Jul 28, 2019, 10:03 AM • Last activity: Jul 28, 2019, 10:44 AM

4 votes

4 answers

1782 views

Is there an alphabetic equivalent of nl or seq?

shell seq nl

I have a file where I'd like to number the lines using "the alphabet" (simple ascii a, b, c, etc.) instead of numbers. So where I could do: nl somefile I'd like to do something like: abc somefile and get output like: ``` a line 1 of file b line 2 of file c line 3 of file ... ``` Even an alphabetic e...

a line 1 of file
b line 2 of file
c line 3 of file
...

Even an alphabetic equivalent of seq could help -- I could use paste to prefix lines. To keep things simple, my file would have 26 or less lines (so abc would not need to wrap letters like ...x, y, z, aa, ab, ac... kind of thing.)

Mike (153 rep)

Jun 15, 2019, 12:42 PM • Last activity: Jun 16, 2019, 01:55 PM

0 votes

1 answers

874 views

"tail" Is Returning the Wrong Requested Number Lines

tail text head nl

I'm trying to use the following approach to subset the output of a manual: man dig | nl | tail -n +389 | head -n 6 However, the output starts at line 304, not line 389. Doing some research, it seems lines marked as "#####################" are not counted. This is very aggravating, and one of my curr...

                                  I'm trying to use the following approach to subset the output of a manual:

    man dig | nl | tail -n +389 | head -n 6

However, the output starts at line 304, not line 389. Doing some research, it seems lines marked as "#####################" are not counted. This is very aggravating, and one of my current books was using this approach to subset number lines. 

Is there any solution to fix the overlooked lines?

George Thompson (3 rep)

Jun 6, 2019, 08:49 AM • Last activity: Jun 6, 2019, 08:52 AM

1 votes

1 answers

598 views

Is it possible to run head & use nl to number the lines?

head nl

When i ran `head file.txt && nl file.txt` it did each command in order of occurance (which makes sense). Is it possible to have the head display with numbered lines, so that this: word word word would become this: 1 word 2 word 3 word

                                  When i ran head file.txt && nl file.txt it did each command in order of occurance (which makes sense). Is it possible to have the head display with numbered lines, so that this: 

    word
    word
    word
would become this:

    1 word
    2 word
    3 word
                                

Jonathon (13 rep)

Jan 19, 2019, 06:57 AM • Last activity: Jan 19, 2019, 08:47 AM

2 votes

2 answers

284 views

How to prepend numerical order on filenames by Zsh/AWK/...?

awk zsh rename nl

I would like to prepend numerical order form 1-777 on the orders given to it. You can loop it through and increment variable in Bash. However, I would like to do it with Zsh and/or Awk. An example follows. Filenames IMG_20161215_081850.jpg IMG_20161215_081851.jpg IMG_20161215_090559.jpg IMG_20161215...

                                  I would like to prepend numerical order form 1-777 on the orders given to it. 
You can loop it through and increment variable in Bash. 
However, I would like to do it with Zsh and/or Awk. 
An example follows. 
Filenames

    IMG_20161215_081850.jpg
    IMG_20161215_081851.jpg
    IMG_20161215_090559.jpg
    IMG_20161215_090601.jpg
    IMG_20161215_091308.jpg

Wanted

    1.IMG_20161215_081850.jpg
    2.IMG_20161215_081851.jpg
    3.IMG_20161215_090559.jpg
    4.IMG_20161215_090601.jpg
    5.IMG_20161215_091308.jpg


OS: Debian 8.5    
                                

Léo Léopold Hertz 준영 (7138 rep)

Dec 23, 2016, 04:44 PM • Last activity: Dec 30, 2016, 01:37 PM

9 votes

4 answers

3822 views

How to increment line counter for line beginning replacements by AWK/...?

text-processing awk nl

I first thought about SED (`sed "s/^/COUNTER \&/" /tmp/1.tex`) but it is designed for a single line, and I cannot increment the counter itself by sed so thinking now `awk` because I have great experiences with `gawk` in integrated approaches. Data What & South Dragon & North Dragon & 5 \\ \hline Wha...

                                  I first thought about SED (sed "s/^/COUNTER \&/" /tmp/1.tex) but it is designed for a single line, and I cannot increment the counter itself by sed so thinking now awk because I have great experiences with gawk in integrated approaches. 
Data

    What & South Dragon & North Dragon    & 5 \\ \hline
    What & South Dragon & North Dragon    & 5 \\ \hline
    What & South Dragon & North Dragon    & 5 \\ \hline

Expected output

    1 & What & South Dragon & North Dragon    & 5 \\ \hline
    2 & What & South Dragon & North Dragon    & 5 \\ \hline
    3 & What & South Dragon & North Dragon    & 5 \\ \hline

OS: Debian 8.5

Léo Léopold Hertz 준영 (7138 rep)

Dec 27, 2016, 07:59 PM • Last activity: Dec 30, 2016, 12:57 PM

1 votes

1 answers

696 views

nl - numbering input in descending order

files numbering nl

Is this possible to number file lines in descending order? That would be something like: nl -i -1 unfortunately this gives me: nl: invalid line number increment: ‘-1’: Numerical result out of range I know that it has no sense in pipe redirection, as `nl` can't guess number of total lines, but if I p...

                                  Is this possible to number file lines in descending order? 

That would be something like:
  
    nl -i -1

unfortunately this gives me:

    nl: invalid line number increment: ‘-1’: Numerical result out of range

I know that it has no sense in pipe redirection, as nl can't guess number of total lines, but if I pass file as an argument it should be quite easy - even it it needs two passes to accomplish the task.

If not nl than maybe some other command.

sZpak (511 rep)

Nov 13, 2016, 06:17 PM • Last activity: Nov 13, 2016, 06:22 PM

0 votes

1 answers

267 views

nl add numbers suffix if regex match?

If I have a text file saying this: Xgrep () { something ; } Xgrep Xgrep Xgrep Xgrep Xgrep I want it to look like this Xgrep () { something ; } Xgrep 12 Xgrep 13 Xgrep 14 Xgrep 15 Xgrep 16 Meaning I want to choose at which number to begin, with suffixes instead of prefixes with one space between (`-s...

                                  If I have a text file saying this:

    Xgrep () { something ; }  
 
    Xgrep
    Xgrep
    Xgrep
    Xgrep
    Xgrep

I want it to look like this
    
    Xgrep () { something ; }  
 
    Xgrep 12
    Xgrep 13
    Xgrep 14
    Xgrep 15
    Xgrep 16

Meaning I want to choose at which number to begin, with suffixes instead of prefixes with one space between (-s " " for a space between). I thought that I could use nl for this, but reading the man page it doesn't seem so. I tried this:

    nl -b pexpr=Xgrep -s " " ~/desktop/test.txt

However this just out put this:

      	Xgrep
      	Xgrep
      	Xgrep
      	Xgrep
      	Xgrep

Which is probably because the regex syntax is wrong but I couldn't find a way for it to match, all other ways it just listed the usage.

[This website] is pretty much exactly what I am trying to do, but in command line form and only with numbers suffix.
                                

DisplayName (12016 rep)

Oct 3, 2015, 03:55 PM • Last activity: Oct 3, 2015, 04:12 PM

2 votes

1 answers

2276 views

How to add a line number follow by a tab to a text file

text-processing nl

I tried using nl -ba -s '\t' full_media > full_media2 But it really did not add the tab, but it added actually the "\t" text after the line number. The file im editing is a CSV file and here by i'm trying to add a new column to the beginning with id.

                                  I tried using 

    nl -ba -s '\t' full_media > full_media2
But it really did not add the tab, but it added actually the "\t" text after the line number. The file im editing is a CSV file and here by i'm trying to add a new column to the beginning with id.

dinesh707 (131 rep)

Feb 9, 2015, 09:14 AM • Last activity: Feb 9, 2015, 09:33 AM

Showing page 1 of 17 total questions