Text formating - sed, awk, shell - linux

I need some assistance trying to build up a variable using a list of exclusions in a file.
So I have a exclude file I am using for rsync that looks like this:
*.log
*.out
*.csv
logs
shared
tracing
jdk*
8.6_Code
rpsupport
dbarchive
inarchive
comms
PR116PICL
**/lost+found*/
dlxwhsr*
regression
tmp
working
investigation
Investigation
dcsserver_weblogic_
dcswebrdtEAR_weblogic_
I need to build up a string to be used as a variable to feed into egrep -v, so that I can use the same exclusion list for rsync as I do when egrep -v from a find -ls.
So I have created this so far to remove all "*" and "/" - and then when it sees certain special characters it escapes them:
cat exclude-list.supt | while read line
do
echo $line | sed 's/\*//g' | sed 's/\///g' | 's/\([.-+_]\)/\\\1/g'
What I need the ouput too look like is this and then export that as a variable:
SEXCLUDE_supt="\.log|\.out|\.csv|logs|shared|PR116PICL|tracing|lost\+found|jdk|8\.6\_Code|rpsupport|dbarchive|inarchive|comms|dlxwhsr|regression|tmp|working|investigation|Investigation|dcsserver\_weblogic\_|dcswebrdtEAR\_weblogic\_"
Can anyone help?

A few issues with the following:
cat exclude-list.supt | while read line
do
echo $line | sed 's/\*//g' | sed 's/\///g' | 's/\([.-+_]\)/\\\1/g'
Sed reads files line by line so cat | while read line;do echo $line | sed is completely redundant also sed can do multiple substitutions by either passing them as a comma separated list or using the -e option so piping to sed three times is two too many. A problem with '[.-+_]' is the - is between . and + so it's interpreted as a range .-+ when using - inside a character class put it at the end beginning or end to lose this meaning like [._+-].
A much better way:
$ sed -e 's/[*/]//g' -e 's/\([._+-]\)/\\\1/g' file
\.log
\.out
\.csv
logs
shared
tracing
jdk
8\.6\_Code
rpsupport
dbarchive
inarchive
comms
PR116PICL
lost\+found
dlxwhsr
regression
tmp
working
investigation
Investigation
dcsserver\_weblogic\_
dcswebrdtEAR\_weblogic\_
Now we can pipe through tr '\n' '|' to replace the newlines with pipes for the alternation ready for egrep:
$ sed -e 's/[*/]//g' -e 's/\([._+-]\)/\\\1/g' file | tr "\n" "|"
\.log|\.out|\.csv|logs|shared|tracing|jdk|8\.6\_Code|rpsupport|dbarchive|...
$ EXCLUDE=$(sed -e 's/[*/]//g' -e 's/\([._+-]\)/\\\1/g' file | tr "\n" "|")
$ echo $EXCLUDE
\.log|\.out|\.csv|logs|shared|tracing|jdk|8\.6\_Code|rpsupport|dbarchive|...
Note: If your file ends with a newline character you will want to remove the final trailing |, try sed 's/\(.*\)|/\1/'.

This might work for you (GNU sed):
SEXCLUDE_supt=$(sed '1h;1!H;$!d;g;s/[*\/]//g;s/\([.-+_]\)/\\\1/g;s/\n/|/g' file)

This should work but I guess there are better solutions. First store everything in a bash array:
SEXCLUDE_supt=$( sed -e 's/\*//g' -e 's/\///g' -e 's/\([.-+_]\)/\\\1/g' exclude-list.supt)
and then process it again to substitute white space:
SEXCLUDE_supt=$(echo $SEXCLUDE_supt |sed 's/\s/|/g')

Related

Linux merging files

I'm doing a linux online course but im stuck with a question, you can find the question below.
You will get three files called a.bf, b.bf and c.bf. Merge the contents of these three files and write it to a new file called abc.bf. Respect the order: abc.bf must contain the contents of a.bf first, followed by those of b.bf, followed by those of c.bf.
Example
Suppose the given files have the following contents:
a.bf contains +++.
b.bf contains [][][][].
c.bf contains <><><>.
The file abc.bf should then have
+++[][][][]<><><>
as its content.
I know how to merge the 3 files but when i use cat my output is:
+++
[][][]
<><><>
When i use paste my output is "+++ 'a lot of spaces' [][][][] 'a lot of spaces' <><><>"
My output that i need is +++[][][][]<><><>, i dont want the spaces between the content. Can someone help me?
What you want to do is delete the newline characters.
With tr:
cat {a,b,c}.bf | tr --delete '\n' > abc.bf
With echo & sed:
echo $(cat {a,b,c}.bf) | sed -E 's/ //g' > abc.bf
With xargs & sed:
<{a,b,c}.bf xargs | sed -E 's/ //g' > abc.bf
Note that sed is only used to remove the spaces.
With cat & sed:
cat {a,b,c}.bf | sed -z 's/\n//g'
echo -n "$(cat a.bf)$(cat b.bf)$(cat c.bf)" > abc.bf
echo -n will not output trailing newlines

How to apply my sed command to some lines of all my files?

I've 95 files that looks like :
2019-10-29-18-00/dev/xx;512.00;0.4;/var/x/xx/xxx
2019-10-29-18-00/dev/xx;512.00;0.68;/xx
2019-10-29-18-00/dev/xx;512.00;1.84;/xx/xx/xx
2019-10-29-18-00/dev/xx;512.00;80.08;/opt/xx/x
2019-10-29-18-00/dev/xx;20480.00;83.44;/var/x/x
2019-10-29-18-00/dev/xx;3584.00;840.43;/var/xx/x
2019-10-30-00-00/dev/xx;2048.00;411.59;/
2019-10-30-00-00/dev/xx;7168.00;6168.09;/usr
2019-10-30-00-00/dev/xx;3072.00;1036.1;/var
2019-10-30-00-00/dev/xx;5120.00;348.72;/tmp
2019-10-30-00-00/dev/xx;20480.00;2033.19;/home
2019-10-30-12-00;/dev/xx;5120.00;348.72;/tmp
2019-10-30-12-00;/dev/hd1;20480.00;2037.62;/home
2019-10-30-12-00;/dev/xx;512.00;0.43;/xx
2019-10-30-12-00;/dev/xx;3584.00;794.39;/xx
2019-10-30-12-00;/dev/xx;512.00;0.4;/var/xx/xx/xx
2019-10-30-12-00;/dev/xx;512.00;0.68;/xx
2019-10-30-12-00;/dev/xx;512.00;1.84;/var/xx/xx
2019-10-30-12-00;/dev/xx;512.00;80.08;/opt/xx/x
2019-10-30-12-00;/dev/xx;20480.00;83.44;/var/xx/xx
2019-10-30-12-00;/dev/x;3584.00;840.43;/var/xx/xx
For some lines I've 2019-10-29-18-00/dev and for some other lines, I've 2019-10-30-12-00;/dev/
I want to add the ; before the /dev/ where it is missing, so for that I use this sed command :
sed 's/\/dev/\;\/dev/'
But How I can apply this command for each lines where the ; is missing ? I try this :
for i in $(cat /home/xxx/xxx/xxx/*.txt | grep -e "00/dev/")
do
sed 's/\/dev/\;\/dev/' $i > $i
done
But it doesn't work... Can you help me ?
Could you please try following with GNU awkif you are ok with it.
awk -i inplace '/00\/dev\//{gsub(/00\/dev\//,"/00;/dev/")} 1' *.txt
sed solution: Tested with GNU sed for few files and it worked fine.
sed -i.bak '/00\/dev/s/00\/dev/00\;\/dev/g' *.txt
This might work for you (GNU sed & parallel):
parallel -q sed -i 's#;*/dev#;/dev#' ::: *.txt
or if you prefer:
sed -i 's#;*/dev#;/dev#' *.txt
Ignore lines with ;/dev.
sed '/;\/dev/{p;d}; s^/dev^;/dev^'
The /;\/dev/ check if the line has ;/dev. If it has ;/dev do: p - print the current line and d - start from the beginning.
You can use any character with s command in sed. Also, there is no need in escaping \;, just ;.
How I can apply this command for each lines where the ; is missing ? I try this
Don't edit the same file redirecting to the same file $i > $i. Think about it. How can you re-write and read from the same file at the same time? You can't, the resulting file will be in most cases empty, as the > $i will "execute" first making the file empty, then sed $i will start running and it will read an empty file. Use a temporary file sed ... "$i" > temp.txt; mv temp.txt "$i" or use gnu extension -i sed option to edit in place.
What you want to do really is:
grep -l '00/dev/' /home/xxx/xxx/xxx/*.txt |
xargs -n1 sed -i '/;\/dev/{p;d}; s^/dev^;/dev^'
grep -l prints list of files that match the pattern, then xargs for each single one -n1 of the files executes sed which -i edits files in place.
grep for filtering can be eliminated in your case, we can accomplish the task with a single sed command:
for f in $(cat /home/xxx/xxx/xxx/*.txt)
do
[[ -f "$f" ]] && sed -Ei '/00\/dev/ s/([^;])(\/dev)/\1;\2/' "$f"
done
The easiest way would be to adjust your regex so that it's looking a bit wider than '/dev/', e.g.
sed -i -E 's|([0-9])/dev|\1;/dev|'
(note that I'm taking advantage of sed's flexible approach to delimiters on substitute. Also, -E changes the group syntax)
Alternatively, sed lets you filter which lines it handles:
sed -i '/[0-9]\/dev/ s/\/dev/;/dev/'
This uses the same substitution you already have but only applied on lines that match the filter regex

Assistance with sed command file please

I created the following bash pipeline that will take the output of "who" and modify it to meet an assignment's requirements
This is the pipline:
who | sed -e "s/\b\(.\)/\u\1/g" | sed 's/[.]/ /g' | sed 's/ Pts\// TTY /g' | sed '1d' | sed -n 's/ .*$/ /gp'
After putting this into a sed file that looks like this:
s/\b\(.\)/\u\1/g
s/[.]/ /g
s/ Pts\// TTY /g
1d
s/ .*$/ /gp
And then running it like such:
who | sed -f sedfile
The output is correct in that everything is in the format of:
firstName lastName TTY (a number)
However each line is printed twice, where the pipeline properly printed each line once
Would anyone happen to know the issue please?
It's the gp at the last line. You're not running with sed -n (no-print), so by default you're running with sed -yesprint (or whatever). Then you hit that gp, which prints, and you get two copies.
Convert to sed -n, or change the gp to just g. Or better still, get rid of it, since the match pattern contains $, so it will only ever run in one place - the end of the line.

Delete empty lines using sed

I am trying to delete empty lines using sed:
sed '/^$/d'
but I have no luck with it.
For example, I have these lines:
xxxxxx
yyyyyy
zzzzzz
and I want it to be like:
xxxxxx
yyyyyy
zzzzzz
What should be the code for this?
You may have spaces or tabs in your "empty" line. Use POSIX classes with sed to remove all lines containing only whitespace:
sed '/^[[:space:]]*$/d'
A shorter version that uses ERE, for example with gnu sed:
sed -r '/^\s*$/d'
(Note that sed does NOT support PCRE.)
I am missing the awk solution:
awk 'NF' file
Which would return:
xxxxxx
yyyyyy
zzzzzz
How does this work? Since NF stands for "number of fields", those lines being empty have 0 fields, so that awk evaluates 0 to False and no line is printed; however, if there is at least one field, the evaluation is True and makes awk perform its default action: print the current line.
sed
'/^[[:space:]]*$/d'
'/^\s*$/d'
'/^$/d'
-n '/^\s*$/!p'
grep
.
-v '^$'
-v '^\s*$'
-v '^[[:space:]]*$'
awk
/./
'NF'
'length'
'/^[ \t]*$/ {next;} {print}'
'!/^[ \t]*$/'
sed '/^$/d' should be fine, are you expecting to modify the file in place? If so you should use the -i flag.
Maybe those lines are not empty, so if that's the case, look at this question Remove empty lines from txtfiles, remove spaces from start and end of line I believe that's what you're trying to achieve.
I believe this is the easiest and fastest one:
cat file.txt | grep .
If you need to ignore all white-space lines as well then try this:
cat file.txt | grep '\S'
Example:
s="\
\
a\
b\
\
Below is TAB:\
\
Below is space:\
\
c\
\
"; echo "$s" | grep . | wc -l; echo "$s" | grep '\S' | wc -l
outputs
7
5
Another option without sed, awk, perl, etc
strings $file > $output
strings - print the strings of printable characters in files.
With help from the accepted answer here and the accepted answer above, I have used:
$ sed 's/^ *//; s/ *$//; /^$/d; /^\s*$/d' file.txt > output.txt
`s/^ *//` => left trim
`s/ *$//` => right trim
`/^$/d` => remove empty line
`/^\s*$/d` => delete lines which may contain white space
This covers all the bases and works perfectly for my needs. Kudos to the original posters #Kent and #kev
The command you are trying is correct, just use -E flag with it.
sed -E '/^$/d'
-E flag makes sed catch extended regular expressions. More info here
You can say:
sed -n '/ / p' filename #there is a space between '//'
You are most likely seeing the unexpected behavior because your text file was created on Windows, so the end of line sequence is \r\n. You can use dos2unix to convert it to a UNIX style text file before running sed or use
sed -r "/^\r?$/d"
to remove blank lines whether or not the carriage return is there.
This works in awk as well.
awk '!/^$/' file
xxxxxx
yyyyyy
zzzzzz
You can do something like that using "grep", too:
egrep -v "^$" file.txt
My bash-specific answer is to recommend using perl substitution operator with the global pattern g flag for this, as follows:
$ perl -pe s'/^\n|^[\ ]*\n//g' $file
xxxxxx
yyyyyy
zzzzzz
This answer illustrates accounting for whether or not the empty lines have spaces in them ([\ ]*), as well as using | to separate multiple search terms/fields. Tested on macOS High Sierra and CentOS 6/7.
FYI, the OP's original code sed '/^$/d' $file works just fine in bash Terminal on macOS High Sierra and CentOS 6/7 Linux at a high-performance supercomputing cluster.
If you want to use modern Rust tools, you can consider:
ripgrep:
cat datafile | rg '.' line with spaces is considered non empty
cat datafile | rg '\S' line with spaces is considered empty
rg '\S' datafile line with spaces is considered empty (-N can be added to remove line numbers for on screen display)
sd
cat datafile | sd '^\n' '' line with spaces is considered non empty
cat datafile | sd '^\s*\n' '' line with spaces is considered empty
sd '^\s*\n' '' datafile inplace edit
Using vim editor to remove empty lines
:%s/^$\n//g
For me with FreeBSD 10.1 with sed worked only this solution:
sed -e '/^[ ]*$/d' "testfile"
inside [] there are space and tab symbols.
test file contains:
fffffff next 1 tabline ffffffffffff
ffffffff next 1 Space line ffffffffffff
ffffffff empty 1 lines ffffffffffff
============ EOF =============
NF is the command of awk you can use to delete empty lines in a file
awk NF filename
and by using sed
sed -r "/^\r?$/d"

Bash - How to remove all white spaces from a given text file?

I want to remove all the white spaces from a given text file.
Is there any shell command available for this ?
Or, how to use sed for this purpose?
I want something like below:
$ cat hello.txt | sed ....
I tried this : cat hello.txt | sed 's/ //g' .
But it removes only spaces, not tabs.
Thanks.
$ man tr
NAME
tr - translate or delete characters
SYNOPSIS
tr [OPTION]... SET1 [SET2]
DESCRIPTION
Translate, squeeze, and/or delete characters from standard
input, writing to standard output.
In order to wipe all whitespace including newlines you can try:
cat file.txt | tr -d " \t\n\r"
You can also use the character classes defined by tr (credits to htompkins comment):
cat file.txt | tr -d "[:space:]"
For example, in order to wipe just horizontal white space:
cat file.txt | tr -d "[:blank:]"
Much simpler to my opinion:
sed -r 's/\s+//g' filename
I think you may use sed to wipe out the space while not losing some infomation like changing to another line.
cat hello.txt | sed '/^$/d;s/[[:blank:]]//g'
To apply into existing file, use following:
sed -i '/^$/d;s/[[:blank:]]//g' hello.txt
Try this:
sed -e 's/[\t ]//g;/^$/d'
(found here)
The first part removes all tabs (\t) and spaces, and the second part removes all empty lines
If you want to remove ALL whitespace, even newlines:
perl -pe 's/\s+//g' file
This answer is similar to other however as some people have been complaining that the output goes to STDOUT i am just going to suggest redirecting it to the original file and overwriting it. I would never normally suggest this but sometimes quick and dirty works.
cat file.txt | tr -d " \t\n\r" > file.txt
Easiest way for me:
echo "Hello my name is Donald" | sed s/\ //g
This is probably the simplest way of doing it:
sed -r 's/\s+//g' filename > output
mv ouput filename
Dude, Just python test.py in your terminal.
f = open('/home/hduser/Desktop/data.csv' , 'r')
x = f.read().split()
f.close()
y = ' '.join(x)
f = open('/home/hduser/Desktop/data.csv','w')
f.write(y)
f.close()
Try this:
tr -d " \t" <filename
See the manpage for tr(1) for more details.
hmm...seems like something on the order of sed -e "s/[ \t\n\r\v]//g" < hello.txt should be in the right ballpark (seems to work under cygwin in any case).

Resources