I want to filter the output of the blkid to get the UUID.
The output of blkid looks like
CASE 1:-
$ blkid
/dev/sda2: LABEL="A" UUID="4CC9-0015"
/dev/sda3: LABEL="B" UUID="70CF-169F"
/dev/sda1: LABEL=" NTFS_partition" UUID="3830C24D30C21234"
In somecases the output of blkid looks like
CASE 2:-
$ blkid
/dev/sda1: UUID="d7ec380e-2521-4fe5-bd8e-b7c02ce41601" TYPE="ext4"
/dev/sda2: UUID="fc54f19a-8ec7-418b-8eca-fbc1af34e57f" TYPE="ext4"
/dev/sda3: UUID="6f218da5-3ba3-4647-a44d-a7be19a64e7a" TYPE="swap"
I want to filter out the UUID.
Using the combination of grep and cut it can be done as
/sbin/blkid | /bin/grep 'sda1' | /bin/grep -o -E 'UUID="[a-zA-Z|0-9|\-]*' | /bin/cut -c 7-
I have tried using awk , grep and cut as below for filtering the UUID
$ /sbin/blkid | /bin/grep 'sda1' | /usr/bin/awk '{print $2}' | /bin/sed 's/\"//g' | cut -c 7-
7ec380e-2521-4fe5-bd8e-b7c02ce41601
The above command(which uses awk) is not reliable since sometimes an extra field such as LABEL may be present in the output of the blkid program as shown in the above output.
What is the best way to create a command using awk which works reliably?
Please post if any other elegant method exits for the job using bin and core utils. I dont want to use perl or python since this has to be run on busybox.
NOTE:-I am using busybox blkid to which /dev/sda1 can not be passed as the args(the version i am using does not support it) hence the grep to filter the line.
UPDATE :- added the CASE 2: -output to show that field position can not be relied upon.
Why are you making it so complex?
Try this:
# blkid -s UUID -o value
d7ec380e-2521-4fe5-bd8e-b7c02ce41601
fc54f19a-8ec7-418b-8eca-fbc1af34e57f
6f218da5-3ba3-4647-a44d-a7be19a64e7a
Or this:
# blkid -s UUID -o value /dev/sda1
d7ec380e-2521-4fe5-bd8e-b7c02ce41601
Install proper blkid package if you don't have it:
sudo apt-get install util-linux
sudo yum install util-linux
For all the UUID's, you can do :
$ blkid | sed -n 's/.*UUID=\"\([^\"]*\)\".*/\1/p'
d7ec380e-2521-4fe5-bd8e-b7c02ce41601
fc54f19a-8ec7-418b-8eca-fbc1af34e57f
6f218da5-3ba3-4647-a44d-a7be19a64e7a
Say, only for a specific sda1:
$ blkid | sed -n '/sda1/s/.*UUID=\"\([^\"]*\)\".*/\1/p'
d7ec380e-2521-4fe5-bd8e-b7c02ce41601
The sed command tries to group the contents present within the double quotes after the UUID keyword, and replaces the entire line with the token.
Here's a short awk solution:
blkid | awk 'BEGIN{FS="[=\"]"} {print $(NF-1)}'
Output:
4CC9-0015
70CF-169F
3830C24D30C21234
Explanation:
BEGIN{FS="[=\"]"} : Use = and " as delimiters
{print $(NF-1)}: NF stands of Number of Fields; here we print the 2nd to last field
This is based on the consistent structure of blkid output: UUID in quotes is at the end of each line.
Alternatively:
blkid | awk 'BEGIN{FS="="} {print $NF}' | sed 's/"//g'
data.txt
/dev/sda2: LABEL="A" UUID="4CC9-0015"
/dev/sda3: LABEL="B" UUID="70CF-169F"
/dev/sda1: LABEL=" NTFS_partition" UUID="3830C24D30C21234"
awk and sed combination
cat data.txt | awk 'BEGIN{FS="UUID";RS="\n"} {print $2}' | sed -e 's/=//' -e 's/"//g'
Explanation:
Set the Field Separator to the string 'UUID', $2 will give the rest output
use sed then to remove the = and " as shown where -e is a switch so that you can give multiple sed commands/expression in one.
All occurrences of " are removed using the ending g option i.e. global.
The question has a "e.t.c" so I'm going to assume python is one of the options ;)
#!/usr/bin/env python3
import subprocess, re, json
# get blkid output
blkid = subprocess.check_output(["blkid"]).decode('utf-8')
devices = []
for line in [x for x in blkid.split('\n') if x]:
parameters = line.split()
for idx, parameter in enumerate(parameters):
if idx is 0:
devices.append({"DEVICE": re.sub(r':$','',parameter)})
continue
key_and_value = parameter.split('=')
devices[-1].update({
key_and_value[0]: re.sub(r'"','',key_and_value[1])
})
uuids = [{dev['DEVICE']: dev['UUID']} for dev in devices if 'UUID' in dev.keys()]
print(json.dumps(uuids, indent=4, sort_keys=True))
Although, this is probably overkill and quite a few error handling/optimization is missing from this script XD
I assume you're using busybox in an initramfs and you are waiting for your e.g. USB drive with the rootfs on it to become available.
You could use the following awk script (busybox awk compliant).
# cat get-ruuid.awk
BEGIN {
ruuid=ENVIRON["RUUID"]
}
/^\/dev\/sd[a-z]/ {
if (index($0, tolower(ruuid)) || index($0, toupper(ruuid))) {
split($1, parts, ":")
printf("%s\n", parts[1])
exit(0) # Return success and stop further scanning.
}
}
END {
exit(1) # If we reach the end, it means RUUID was not found.
}
Call it as follows from e.g. the init script; this is not the most ideal way.
# The UUID of your root partition
export RUUID="<put proper uuid value here>"
for x in 1, 2, 3, 4, 5 ; do
mdev -s
found=$(blkid | awk -f ./get-ruuid.awk)
test -z $found || break; # If no longer zero length, break the loop.
sleep 1
done
But if this is the only reason why you would want to have an initramfs, I would use the 'root=PARTUUID=... waitroot' Linux kernel command line option. Check the kernel docs and sources.
Get the proper PARTUUID (NOT UUID) of your root partition with the blkid command.
Related
I have a plaintext file containing multiple instances of the pattern $$DATABASE_*$$ and the asterisk could be any string of characters. I'd like to replace the entire instance with whatever is in the asterisk portion, but lowercase.
Here is a test file:
$$DATABASE_GIBSON$$
test me $$DATABASE_GIBSON$$ test me
$$DATABASE_GIBSON$$ test $$DATABASE_GIBSON$$ test
$$DATABASE_GIBSON$$ $$DATABASE_GIBSON$$$$DATABASE_GIBSON$$
Here is the desired output:
gibson
test me gibson test me
gibson test gibson test
gibson gibsongibson
How do I do this with sed/awk/tr/perl?
Here's the perl version I ended up using.
perl -p -i.bak -e 's/\$\$DATABASE_(.*?)\$\$/lc($1)/eg' inputFile
Unfortunately there's no easy, foolproof way with awk, but here's one approach:
$ cat tst.awk
{
gsub(/[$][$]/,"\n")
head = ""
tail = $0
while ( match(tail, "\nDATABASE_[^\n]+\n") ) {
head = head substr(tail,1,RSTART-1)
trgt = substr(tail,RSTART,RLENGTH)
tail = substr(tail,RSTART+RLENGTH)
gsub(/\n(DATABASE_)?/,"",trgt)
head = head tolower(trgt)
}
$0 = head tail
gsub("\n","$$")
print
}
$ cat file
The quick brown $$DATABASE_FOX$$ jumped over the lazy $$DATABASE_DOG$$s back.
The grey $$DATABASE_SQUIRREL$$ ate $$DATABASE_NUT$$s under a $$DATABASE_TREE$$.
Put a dollar $$DATABASE_DOL$LAR$$ in the $$ string.
$ awk -f tst.awk file
The quick brown fox jumped over the lazy dogs back.
The grey squirrel ate nuts under a tree.
Put a dollar dol$lar in the $$ string.
Note the trick of converting $$ to a newline char so we can negate that char in the match(RE), without that (i.e. if we used ".+" instead of "[^\n]+") then due to greedy RE matching if the same pattern appeared twice on one input line the matching string would extend from the start of the first pattern to the end of the second pattern.
This one works with complicated examples.
perl -ple 's/\$\$DATABASE_(.*?)\$\$/lc($1)/eg' filename.txt
And for simpler examples :
echo '$$DATABASE_GIBSON$$' | sed 's#$$DATABASE_\(.*\)\$\$#\L\1#'
in sed, \L means lower case (\E to stop if needed)
Using awk alone:
> echo '$$DATABASE_AWESOME$$' | awk '{sub(/.*_/,"");sub(/\$\$$/,"");print tolower($0);}'
awesome
Note that I'm in FreeBSD, so this is not GNU awk.
But this can be done using bash alone:
[ghoti#pc ~]$ foo='$$DATABASE_AWESOME$$'
[ghoti#pc ~]$ foo=${foo##*_}
[ghoti#pc ~]$ foo=${foo%\$\$}
[ghoti#pc ~]$ foo=${foo,,}
[ghoti#pc ~]$ echo $foo
awesome
Of the above substitutions, all except the last one (${foo,,}) will work in standard Bourne shell. If you don't have bash, you can instead do use tr for this step:
$ echo $foo
AWESOME
$ foo=$(echo "$foo" | tr '[:upper:]' '[:lower:]')
$ echo $foo
awesome
$
UPDATE:
Per comments, it seems that what the OP really wants is to strip the substring out of any text in which it is included -- that is, our solutions need to account for the possibility of leading or trailing spaces, before or after the string he provided in his question.
> echo 'foo $$DATABASE_KITTENS$$ bar' | sed -nE '/\$\$[^$]+\$\$/{;s/.*\$\$DATABASE_//;s/\$\$.*//;p;}' | tr '[:upper:]' '[:lower:]'
kittens
And if you happen to have pcregrep on your path (from the devel/pcre FreeBSD port), you can use that instead, with lookaheads:
> echo 'foo $$DATABASE_KITTENS$$ bar' | pcregrep -o '(?!\$\$DATABASE_)[A-Z]+(?=\$\$)' | tr '[:upper:]' '[:lower:]'
kittens
(For Linux users reading this: this is equivalent to using grep -P.)
And in pure bash:
$ shopt -s extglob
$ foo='foo $$DATABASE_KITTENS$$ bar'
$ foo=${foo##*(?)\$\$DATABASE_}
$ foo=${foo%%\$\$*(?)}
$ foo=${foo,,}
$ echo $foo
kittens
Note that NONE of these three updated solutions will handle situations where multiple tagged database names exist in the same line of input. That's not stated as a requirement in the question either, but I'm just sayin'....
You can do this in a pretty foolproof way with the supercool command cut :)
echo '$$DATABASE_AWESOME$$' | cut -d'$' -f3 | cut -d_ -f2 | tr 'A-Z' 'a-z'
This might work for you (GNU sed):
sed 's/$\$/\n/g;s/\nDATABASE_\([^\n]*\)\n/\L\1/g;s/\n/$$/g' file
Here is the shortest (GNU) awk solution I could come up with that does everything requested by the OP:
awk -vRS='[$][$]DATABASE_([^$]+[$])+[$]' '{ORS=tolower(substr(RT,12,length(RT)-13))}1'
Even if the string indicated with the asterix (*) contained one or more single Dollar signs ($) and/or linebreaks this soultion should still work.
awk '{gsub(/\$\$DATABASE_GIBSON\$\$/,"gibson")}1' file
gibson
test me gibson test me
gibson test gibson test
gibson gibsongibson
echo $$DATABASE_WOOLY$$ | awk '{print tolower($0)}'
awk will take what ever input, in this case the first agurment, and use the tolower function and return the results.
For your bash script you can do something like this and use the variable DBLOWER
DBLOWER=$(echo $$DATABASE_WOOLY$$ | awk '{print tolower($0)}');
I have a CSV. I want to edit the 35th field of the CSV and write the change back to the 35th field. This is what I am doing on bash:
awk -F "," '{print $35}' test.csv | sed -i 's/^0/+91/g'
so, I am pulling the 35th entry using awk and then replacing the "0" in the starting position in the string with "+91". This one works perfet and I get desired output on the console.
Now I want this new entry to get written in the file. I am thinking of sed's "in -place" replacement feature but this fetuare needs and input file. In above command, I cannot provide input file because my primary command is awk and sed is taking the input from awk.
Thanks.
You should choose one of the two tools. As for sed, it can be done as follows:
sed -ri 's/^(([^,]*,){34})0([^,]*)/\1+91\3/' test.csv
Not sure about awk, but #shellter's comment might help with that.
The in-place feature of sed is misnamed, as it does not edit the file in place. Instead, it creates a new file with the same name. eg:
$ echo foo > foo
$ ln -f foo bar
$ ls -i foo bar # These are the same file
797325 bar 797325 foo
$ echo new-text > foo # Changes bar
$ cat bar
new-text
$ printf '/new/s//newer\nw\nq\n' | ed foo # Edit foo "in-place"; changes bar
9
newer-text
11
$ cat bar
newer-text
$ ls -i foo bar # Still the same file
797325 bar 797325 foo
$ sed -i s/new/newer/ foo # Does not edit in-place; creates a new file
$ ls -i foo bar
797325 bar 792722 foo
Since sed is not actually editing the file in place, but writing a new file and then renaming it to the old file, you might as well do the same.
awk ... test.csv | sed ... > test.csv.1 && mv test.csv.1 test.csv
There is the misperception that using sed -i somehow avoids the creation of the temporary file. It does not. It just hides the fact from you. Sometimes abstraction is a good thing, but other times it is unnecessary obfuscation. In the case of sed -i, it is the latter. The shell is really good at file manipulation. Use it as intended. If you do need to edit a file in place, don't use the streaming version of ed; just use ed
So, it turned out there are numerous ways to do it. I got it working with sed as below:
sed -i 's/0\([0-9]\{10\}\)/\+91\1/g' test.csv
But this is little tricky as it will edit any entry which matches the criteria. however in my case, It is working fine.
Similar implementation of above logic in perl:
perl -p -i -e 's/\b0(\d{10})\b/\+91$1/g;' test.csv
Again, same caveat as mentioned above.
More precise way of doing it as shown by Lev Levitsky because it will operate specifically on the 35th field
sed -ri 's/^(([^,]*,){34})0([^,]*)/\1+91\3/g' test.csv
For more complex situations, I will have to consider using any of the csv modules of perl.
Thanks everyone for your time and input. I surely know more about sed/awk after reading your replies.
This might work for you:
sed -i 's/[^,]*/+91/35' test.csv
EDIT:
To replace the leading zero in the 35th field:
sed 'h;s/[^,]*/\n&/35;/\n0/!{x;b};s//+91/' test.csv
or more simply:
|sed 's/^\(\([^,]*,\)\{34\}\)0/\1+91/' test.csv
If you have moreutils installed, you can simply use the sponge tool:
awk -F "," '{print $35}' test.csv | sed -i 's/^0/+91/g' | sponge test.csv
sponge soaks up the input, closes the input pipe (stdin) and, only then, opens and writes to the test.csv file.
As of 2015, moreutils is available in package repositories of several major Linux distributions, such as Arch Linux, Debian and Ubuntu.
Another perl solution to edit the 35th field in-place:
perl -i -F, -lane '$F[34] =~ s/^0/+91/; print join ",",#F' test.csv
These command-line options are used:
-i edit the file in-place
-n loop around every line of the input file
-l removes newlines before processing, and adds them back in afterwards
-a autosplit mode – split input lines into the #F array. Defaults to splitting on whitespace.
-e execute the perl code
-F autosplit modifier, in this case splits on ,
#F is the array of words in each line, indexed starting with 0
$F[34] is the 35 element of the array
s/^0/+91/ does the substitution
The following command is correctly changing the contents of 2 files.
sed -i 's/abc/xyz/g' xaa1 xab1
But what I need to do is to change several such files dynamically and I do not know the file names. I want to write a command that will read all the files from current directory starting with xa* and sed should change the file contents.
I'm surprised nobody has mentioned the -exec argument to find, which is intended for this type of use-case, although it will start a process for each matching file name:
find . -type f -name 'xa*' -exec sed -i 's/asd/dsg/g' {} \;
Alternatively, one could use xargs, which will invoke fewer processes:
find . -type f -name 'xa*' | xargs sed -i 's/asd/dsg/g'
Or more simply use the + exec variant instead of ; in find to allow find to provide more than one file per subprocess call:
find . -type f -name 'xa*' -exec sed -i 's/asd/dsg/g' {} +
Better yet:
for i in xa*; do
sed -i 's/asd/dfg/g' $i
done
because nobody knows how many files are there, and it's easy to break command line limits.
Here's what happens when there are too many files:
# grep -c aaa *
-bash: /bin/grep: Argument list too long
# for i in *; do grep -c aaa $i; done
0
... (output skipped)
#
You could use grep and sed together. This allows you to search subdirectories recursively.
Linux: grep -r -l <old> * | xargs sed -i 's/<old>/<new>/g'
OS X: grep -r -l <old> * | xargs sed -i '' 's/<old>/<new>/g'
For grep:
-r recursively searches subdirectories
-l prints file names that contain matches
For sed:
-i extension (Note: An argument needs to be provided on OS X)
Those commands won't work in the default sed that comes with Mac OS X.
From man 1 sed:
-i extension
Edit files in-place, saving backups with the specified
extension. If a zero-length extension is given, no backup
will be saved. It is not recommended to give a zero-length
extension when in-place editing files, as you risk corruption
or partial content in situations where disk space is exhausted, etc.
Tried
sed -i '.bak' 's/old/new/g' logfile*
and
for i in logfile*; do sed -i '.bak' 's/old/new/g' $i; done
Both work fine.
#PaulR posted this as a comment, but people should view it as an answer (and this answer works best for my needs):
sed -i 's/abc/xyz/g' xa*
This will work for a moderate amount of files, probably on the order of tens, but probably not on the order of millions.
Another more versatile way is to use find:
sed -i 's/asd/dsg/g' $(find . -type f -name 'xa*')
I'm using find for similar task. It is quite simple: you have to pass it as an argument for sed like this:
sed -i 's/EXPRESSION/REPLACEMENT/g' `find -name "FILE.REGEX"`
This way you don't have to write complex loops, and it is simple to see, which files you are going to change, just run find before you run sed.
u can make
'xxxx' text u search and will replace it with 'yyyy'
grep -Rn '**xxxx**' /path | awk -F: '{print $1}' | xargs sed -i 's/**xxxx**/**yyyy**/'
There's some good answers above. I thought I'd throw in one more that is succinct and parallelizable, using GNU parallel, which I often prefer to xargs:
parallel sed -i 's/abc/xyz/g' {} ::: xa*
Combine this with the -j N option to run N jobs in parallel.
If you are able to run a script, here is what I did for a similar situation:
Using a dictionary/hashMap (associative array) and variables for the sed command, we can loop through the array to replace several strings. Including a wildcard in the name_pattern will allow to replace in-place in files with a pattern (this could be something like name_pattern='File*.txt' ) in a specific directory (source_dir).
All the changes are written in the logfile in the destin_dir
#!/bin/bash
source_dir=source_path
destin_dir=destin_path
logfile='sedOutput.txt'
name_pattern='File.txt'
echo "--Begin $(date)--" | tee -a $destin_dir/$logfile
echo "Source_DIR=$source_dir destin_DIR=$destin_dir "
declare -A pairs=(
['WHAT1']='FOR1'
['OTHER_string_to replace']='string replaced'
)
for i in "${!pairs[#]}"; do
j=${pairs[$i]}
echo "[$i]=$j"
replace_what=$i
replace_for=$j
echo " "
echo "Replace: $replace_what for: $replace_for"
find $source_dir -name $name_pattern | xargs sed -i "s/$replace_what/$replace_for/g"
find $source_dir -name $name_pattern | xargs -I{} grep -n "$replace_for" {} /dev/null | tee -a $destin_dir/$logfile
done
echo " "
echo "----End $(date)---" | tee -a $destin_dir/$logfile
First, the pairs array is declared, each pair is a replacement string, then WHAT1 will be replaced for FOR1 and OTHER_string_to replace will be replaced for string replaced in the file File.txt. In the loop the array is read, the first member of the pair is retrieved as replace_what=$i and the second as replace_for=$j. The find command searches in the directory the filename (that may contain a wildcard) and the sed -i command replaces in the same file(s) what was previously defined. Finally I added a grep redirected to the logfile to log the changes made in the file(s).
This worked for me in GNU Bash 4.3 sed 4.2.2 and based upon VasyaNovikov's answer for Loop over tuples in bash.
The Silver Searcher Solution
I'm adding another option for those people who don't know about the amazing tool called The Silver Searcher (command line tool is ag).
Note: You can use grep and other tools to do the same thing here, but The Silver Searcher is fantastic :)
TLDR
ag -l 'abc' | xargs sed -i 's/abc/xyz/g'
Install The Silver Searcher
sudo apt install silversearcher-ag # Debian / Ubuntu
sudo pacman -S the_silver_searcher # Arch / EndeavourOS
sudo yum install epel-release the_silver_searcher # RHEL / CentOS
Demo Files
Paste the following into your terminal to create some demonstration files:
mkdir /tmp/food
cd /tmp/food
content="Everybody loves to abc this food!"
echo "$content" > ./milk
echo "$content" > ./bread
mkdir ./fastfood
echo "$content" > ./fastfood/pizza
echo "$content" > ./fastfood/burger
mkdir ./fruit
echo "$content" > ./fruit/apple
echo "$content" > ./fruit/apricot
Using 'ag'
The following ag command will recursively find all the files that contain the string 'abc'. It ignores the .git directory, .gitignore files, and other ignore files:
$ ag 'abc'
milk
1:Everybody loves to abc this food!
bread
1:Everybody loves to abc this food!
fastfood/burger
1:Everybody loves to abc this food!
fastfood/pizza
1:Everybody loves to abc this food!
fruit/apple
1:Everybody loves to abc this food!
fruit/apricot
1:Everybody loves to abc this food!
To just list the files that contain the string 'abc', use the -l switch:
$ ag -l 'abc'
bread
fastfood/burger
fastfood/pizza
fruit/apricot
milk
fruit/apple
Changing Multiple Files
Finally, using xargs and sed, we can replace the 'abc' string with another string:
ag -l 'abc' | xargs sed -i 's/abc/eat/g'
In the above command, ag is listing all the files that contain the string 'abc'. The xargs command is splitting the file names and piping them individually into the sed command.
I have the following sed command. I need to execute the below command in single line
cat File | sed -n '
/NetworkName/ {
N
/\n.*ims3/ p
}' | sed -n 1p | awk -F"=" '{print $2}'
I need to execute the above command in single line. can anyone please help.
Assume that the contents of the File is
System.DomainName=shayam
System.Addresses=Fr6
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=AS
System.DomainName=ims5.com
System.DomainName=Ram
System.Addresses=Fr9
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=Peer
System.DomainName=ims7.com
System.DomainName=mani
System.Addresses=Hello
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=Peer
System.DomainName=ims3.com
And after executing the command you will get only peer as the output. Can anyone please help me out?
You can use a single nawk command. And you can lost the useless cat
nawk -F"=" '/NetworkName/{n=$2;getline;if($2~/ims3/){print n} }' file
You can use sed as well as proposed by others, but i prefer less regex and less clutter.
The above save the value of the network name to "n". Then, get the next line and check the 2nd field against "ims3". If matched, then print the value of "n".
Put that code in a separate .sh file, and run it as your single-line command.
cat File | sed -n '/NetworkName/ { N; /\n.*ims3/ p }' | sed -n 1p | awk -F"=" '{print $2}'
Assuming that you want the network name for the domain ims3, this command line works without sed:
grep -B 1 ims3 File | head -n 1 | awk -F"=" '{print $2}'
So, you want the network name where the domain name on the following line includes 'ims3', and not the one where the following line includes 'ims7' (even though the network names in the example are the same).
sed -n '/NetworkName/{N;/ims3/{s/.*NetworkName=\(.*\)\n.*/\1/p;};}' File
This avoids abuse of felines, too (not to mention reducing the number of commands executed).
Tested on MacOS X 10.6.4, but there's no reason to think it won't work elsewhere too.
However, empirical evidence shows that Solaris sed is different from MacOS sed. It can all be done in one sed command, but it needs three lines:
sed -n '/NetworkName/{N
/ims3/{s/.*NetworkName=\(.*\)\n.*/\1/p;}
}' File
Tested on Solaris 10.
You just need to put -e pretty much everywhere you'd break the command at a newline or have a semicolon. You don't need the extra call to sed or awk or cat.
sed -n -e '/NetworkName/ {' -e 'N' -e '/\n.*ims3/ s/[^\n]*=\(.*\).*/\1/P' -e '}' File
My script takes a file name in the form R#TYPE.TXT (# is a number and TYPE is two or three characters).
I want my script to give me TYPE. What should I do to get it? Guess I need to use awk and sed.
I'm using /bin/sh (which is a requirement)
you can use awk
$ echo R1CcC.TXT | awk '{sub(/.*[0-9]/,"");sub(".TXT","")}{print}'
CcC
or
$ echo R1CcC.TXT | awk '{gsub(/.*[0-9]|\.TXT$/,"");print}'
CcC
and if sed is really what you want
$ echo R9XXX.TXT | sed 's/R[0-9]\(.*\)\.TXT/\1/'
XXX
I think this is what you are looking for.
$ echo R3cf.txt | sed "s/.[0-9]\(.*\)\..*/\1/"
cf
If txt is always upper case and the filename always starts with R you could do something like.
$ echo R3cf.txt | sed "s/R[0-9]\(.*\)\.TXT/\1/"
You can use just the shell (depending what shell your bin/sh is:
f=R9ABC.TXT
f="${f%.TXT}" # remove the extension
type="${f#R[0-9]}" # remove the first bit
echo "$type" # ==> ABC