Example: In my folder
C:\users\inputfiles contains
file1.txt
file2.txt
file3.txt with headers.
Need to remove the header in each file and move the data into same file( File name should not change) by using shell script
sed and tail will help you with this.
No output redirection is required if sed is used.
sed -i '1d' filename
If you're using tail then use a intermediate tmp file to have the contents stored and then move that content of tmp file to the original file name.
tail -n +2 "$FILE" > "$FILE.tmp" && mv "$FILE.tmp" "$FILE"
tail will work faster compared to sed.
Run This Command For Each of your File.
tail -n +2 "$FILE" > "$FILE.tmp" && mv "$FILE.tmp" "$FILE"
It should work.
I assume the number of lines of the headers are all the same: 2
Give a try to this, to remove the lines before the 3 for each files with .txt suffix in current directory:
sed -n -i '3,$ p' *.txt
-i: modify each file directly
Related
I am trying to save a list of files in a directory into a single file using
ls > output.txt
Let's say we have in the directory:
a.txt
b.txt
c.txt
I want to modify the names of these files in the output.txt to be like:
1a.txt$
1b.txt$
1c.txt$
Another easy way use AWK to change content and save to file via .tmp
This script will print content how you want. Just add "1" and "$" to begining and ending accordingly.
cat output.txt | awk '{print "1"$1"$"}'
And then you can save to original file as you want by extending command && (if success then next )
cat output.txt | awk '{print "1"$1"$"}' > output.txt.tmp && mv output.txt.tmp output.txt
#!/bin/sh -x
for f in *.txt
do
nf=$(echo "${f}" | sed 's#^#1#')
mv -v "${f}" "${nf}"
done
So, disclaimer: I am pretty new to using bash and zsh, so there is a chance the answer is really simple. Nonetheless. I checked previous postings and couldn't find anything. (edit: I have tried this in both bash and zsh shells- same problem.)
I have a directory with many files and am trying to remove the first line from each file.
So say the directory contains: file1.txt file2.txt file3.txt ... etc.
I am using the sed command (non-GNU):
sed -i -e "1d" *.txt
For some reason, this is only removing the first line of the first file. I thought that the *.txt would affect all files matching the pattern in directory. Strangely, it is creating the file duplicates with -e appended, but both the duplicate and original are the same.
I tried this with other commands (e.g. ls *.txt) and it works fine. Is there something about sed I am missing?
Thank you in advance.
Different versions of sed in differing operating systems support various parameters.
OpenBSD (5.4) sed
The -i flag is unavailable. You can use the following /bin/sh syntax:
for i in *.txt
do
f=`mktemp -p .`
sed -e "1d" "${i}" > "${f}" && mv -- "${f}" "${i}"
done
FreeBSD (11-CURRENT) sed
The -i flag requires an extension, even if it's empty. Thus must be written as sed -i "" -e "1d" *.txt
GNU sed
This looks to see if the argument following -i is another option (or possibly a command). If so, it assumes an in-place modification. If it appears to be a file extension such as ".bak", it will rename the original with the ".bak" and then modify it into the original file's name.
There might be other variations on other platforms, but those are the three I have at hand.
use it without -e !
for one file use:
sed -i '1d' filename
for all files use :
sed -i '1d' *.txt
or
files=/path/to/files/*.extension ; for var in $files ; do sed -i '1d' $var ; done
.for me i use ubuntu and debian based systems , this method is working for me 100% , but for other platformes i'm not sure , so this is other method :
replace first line with emty pattern , and remove empty lines , (double commands):
for files in $(ls /path/to/files/*.txt); do sed -i "s/$(head -1 "$files")//g" "$files" ; sed -i '/^$/d' "$files" ; done
Note: if your files contain splash '/' , then it will give error , so in this case sed command should look like this ( sed -i "s[$(head -1 "$files")[[g" )
hope that's what you're looking for :)
The issue here is that the line number isn't reset when sed opens a new file, so 1 only matches the first line of the first file.
One solution is to use a shell loop, calling sed once for each file. Gumnos' answer shows how to do this in the most widely compatible way, although if you have a version of sed supporting the -i flag, you could do this instead:
for i in *.txt; do
sed -i.bak '1d' "$i"
done
It is possible to avoid creating the backup file by passing an empty suffix but personally, I don't think it's such a bad thing. One day you'll be grateful for it!
It appears that you're not working with GNU tools but if you were, I would recommend using GNU awk for this task. The variable FNR is useful here, as it keeps track of the record number for each file individually, allowing you to do this:
gawk -i inplace 'FNR>1' *.txt
Using the inplace extension, this allows you to remove the first line from each of your files, by only printing the lines where FNR is greater than 1.
Testing it out:
$ seq 5 > file1
$ seq 5 > file2
$ gawk -i inplace 'FNR>1' file1 file2
$ cat file1
2
3
4
5
$ cat file2
2
3
4
5
The last argument you are passing to the Sed is the problem
try something like this.
var=(`find *txt`)
for file in "${var[#]}"
do
sed -i -e 1d $file
done
This did the trick for me.
I have hundreds of text files in one directory. For all files, I want to delete all the lines that begin with HETATM. I would need a csh or bash code.
I would think you would use grep, but I'm not sure.
Use sed like this:
sed -i -e '/^HETATM/d' *.txt
to process all files in place.
-i means "in place".
-e means to execute the command that follows.
/^HETATM/ means "find lines starting with HETATM", and the following d means "delete".
Make a backup first!
If you really want to do it with grep, you could do this:
#!/bin/bash
for f in *.txt
do
grep -v "^HETATM" "%f" > $$.tmp && mv $$.tmp "$f"
done
It makes a temporary file of the output from grep (in file $$.tmp) and only overwrites your original file if the command executes successfully.
Using the -v option of grep to get all the lines that do not match:
grep -v '^HETATM' input.txt > output.txt
I suspect this is an easy one. I have a directory of files and I need the last line from each file grouped into a new file.
I used:
tail -q myFile_seed*.csv > output.csv
But the output file is one long line. Is there a simple way to redirect with newlines so that each file is on its own line?
It appears that your files do not have the usual \r\n appended to the final line of the file. In this case, you'll need to handle each file separately, rather than have tail process them all at once.
for f in myfile_seed*.csv; do
tail -n 1 "$f"
printf "\n"
done > output.csv
You can do:
tail -q -n 1 myFile_seed*.csv > output.csv
Other option would be in one line;
ls myFile_seed*.csv | xargs -ifile sh -c "tail -n 1 file; echo " > output.csv
I am trying to modify a bash script to remove a glob of malicious code from a large number of files.
The community will benefit from this, so here it is:
#!/bin/bash
grep -r -l 'var createDocumentFragm' /home/user/Desktop/infected_site/* > /home/user/Desktop/filelist.txt
for i in $(cat /home/user/Desktop/filelist.txt)
do
cp -f $i $i.bak
done
for i in $(cat /home/user/Desktop/filelist.txt)
do
$i | sed 's/createDocumentFragm.*//g' > $i.awk
awk '/<\/SCRIPT>/{p=1;print}/<\/script>/{p=0}!p'
This is where the script bombs out with this message:
+ for i in '$(cat /home/user/Desktop/filelist.txt)'
+ sed 's/createDocumentFragm.*//g'
+ /home/user/Desktop/infected_site/index.htm
I get 2 errors and the script stops.
/home/user/Desktop/infected_site/index.htm: line 1: syntax error near unexpected token `<'
/home/user/Desktop/infected_site/index.htm: line 1: `<html><head><script>(function (){ '
I have the first 2 parts done.
The files containing createDocumentfragm have been enumerated in a text file correctly.
The files in the textfile.txt have been duplicated, in their original location with a .bak added to them IE: infected_site/some_directory/infected_file.htm and infected_file.htm.bak
effectively making sure we have a backup.
All I need to do now is write an AWK command that will use the list of files in filelist.txt, use the entire glob of malicious text as a pattern, and remove it from the files. Using just the uppercase script as the starting point, and the lower case script is too generic and could delete legitimate text
I suspect this may help me, but I don't know how to use it correctly.
http://backreference.org/2010/03/13/safely-escape-variables-in-awk/
Once I have this part figured out, and after you have verified that the files weren't mangled you can do this to clean out the bak files:
for i in $(cat /home/user/Desktop/filelist.txt)
do
rm -f $i.bak
done
Several things:
You have:
$i | sed 's/var createDocumentFragm.*//g' > $i.awk
You should probably meant this (using your use of cat which we'll talk about in a moment):
cat $i | sed 's/var createDocumentFragm.*//g' > $i.awk
You're treating each file in your file list as if it was a command and not a file.
Now, about your use of cat. If you're using cat for almost anything but concatenating multiple files together, you probably are doing something not quite right. For example, you could have done this:
sed 's/var createDocumentFragm.*//g' "$i" > $i.awk
I'm also a bit confused about the awk statement. Exactly what file are you using awk on? Your awk statement is using STDIN and STDOUT, so it's reading file names from the for loop and then printing the output on the screen. Is the sed statement suppose to feed into the awk statement?
Note that I don't have to print out my file to STDOUT, then pipe that into sed. The sed command can take the file name directly.
You also want to avoid for loops over a list of files. That is very inefficient, and can cause problems with the command line getting overloaded. Not a big issue today, but can affect you when you least suspect it. What happens is that your $(cat /home/user/Desktop/filelist.txt) must execute first before the for loop can even start.
A little rewriting of your program:
cd ~/Desktop
grep -r -l 'var createDocumentFragm' infected_site/* > filelist.txt
while read file
do
cp -f "$file" "$file.bak"
sed 's/var createDocumentFragm.*//g' "$file" > "$i.awk"
awk '/<\/SCRIPT>/{p=1;print}/<\/script>/{p=0}!p'
done < filelist.txt
We can use one loop, and we made it a while loop. I could even feed the grep into that while loop:
grep -r -l 'var createDocumentFragm' infected_site/* | while read file
do
cp -f "$file" "$file.bak"
sed 's/var createDocumentFragm.*//g' "$file" > "$i.awk"
awk '/<\/SCRIPT>/{p=1;print}/<\/script>/{p=0}!p'
done < filelist.txt
and then I don't even have to create a temporary file.
Let me know what's going on with the awk. I suspect you wanted something like this:
grep -r -l 'var createDocumentFragm' infected_site/* | while read file
do
cp -f "$file" "$file.bak"
sed 's/var createDocumentFragm.*//g' "$file" \
| awk '/<\/SCRIPT>/{p=1;print}/<\/script>/{p=0}!p' > "$i.awk"
done < filelist.txt
Also note I put quotes around file names. This helps prevent problems if file name has a space in it.