Hey basically right now my program gives me this output:
BLABLABLA
TEXTEXOUAIGJIOAJGOAJFKJAFKLAJKLFJKL
TEXT
MORE TEXT OF RANDOM CHARACTER OVER LIMIT
which is a result of for loop. Now here's what i want:
if the string raches over 10 characters, cut the rest and add two dots & colon to the end "..:"
otherwise (if the string has less than 10 characters) fill the gap with spaces so they're alligned
so on the example i provided i'd want something like this as output:
BLABLABLA :
TEXTEXOUA..:
TEXT :
MORE TEXT..:
I also solved the first part of the problem (when its over 10 characters), only the second one gives me trouble.
AMOUNT=definition here, just simplyfying so not including it
for (( i=1; i<="$AMOUNT"; i++ )); do
STRING=definition here, just simplyfying so not including it
DOTS="..:"
STRING_LENGTH=`echo -n "$STRING" | wc -c`
if [ "$STRING_LENGTH" -gt 10 ]
then
#Takes
STRING=`echo -n "${STRING:0:10}"$DOTS`
else
#now i dont know what to do here, how can i take my current $STRING
#and add spaces " " until we reach 10 characters. Any ideas?
fi
Bash provides a simple way to get the length of a string stored in a variable: ${#STRING}
STRING="definition here, just simplyfying so not including it"
if [ ${#STRING} -gt 10 ]; then
STR12="${STRING:0:10}.."
else
STR12="$STRING " # 12 spaces here
STR12="${STR12:0:12}"
fi
echo "$STR12:"
The expected output you posted doesn't match the requirements in the question. I tried to follow the requirements and ignored the sample expected output and the code you posted.
Use printf:
PADDED_STRING=$(printf %-10s $STRING)
Related
I have an array that has three types of data in it, integer, integer/integer, and the string value.
I have shown a sample below.
myarr = (2301/2320,Team Lifeline, 2311, 7650/7670, 232)
I have the following algorithm that I want to come up with.
For index in myarr
if index contains data as number1/number2; then
create an array, "mynumbers" to hold all the numbers starting from number1 to number2
else if index is a string
add it in "mystrarr"
else
add it in "myintarr"
done
For the first case, if I have an enter in the myarr as 2301/2320,
then the mynumbers as shown in the pseudocode will have entries from {2301, 2302, ... , 2320}. I am not able to understand on how to parse the entry in myarr and identify that it has a / in the array.
For the second situation, I am also not sure on how to identify if the entry in the myarr and know it is a string. mystrarr should have {Team Lifeline}.
For the final case, the myintarr should have {2311, 232}.
Any help would be appreciated. I am very new to shell script.
Stack Overflow is not a coding service.... but I was bored so here you go...
#!/bin/bash
myarr=(2301/2320 'Team Lifeline' 2311 7650/7670 232)
for element in "${myarr[#]}"; do
if [[ $element =~ ^[0-9]+/[0-9]+$ ]]; then
range="{${element%/*}..${element##*/}}"
mynumbers=( $(eval "echo $range") )
elif [ $element -eq $element ] 2>> /dev/null; then
intarr+=( $element )
else
strarr+=( "$element" )
fi
done
echo "mynumbers = ${mynumbers[*]}"
echo "intarr = ${intarr[*]}"
echo "strarr = ${strarr[*]}"
A lot to unpack here for inexperienced. So ask questions where I didn't cover anything. Things to note:
All assignments there are no spaces around =.
Array assignments are of the format ( element1 element2 ... )
Appending to arrays with +=(...) format
Looping through array elements for element in "${myarr[#]}"
Note that the array generated by 7650/7670 will overwrite the array generated by 2301/2320. I assume you have some kind of plan for this array, so I didn't do anything to stop it from being overwritten.
More details
This line is validating the format for 111/222:
if [[ $element =~ ^[0-9]+/[0-9]+$ ]]; then
[[ x =~ x ]] performs a regex comparison and this regex essentially just means:
^ - beginning of the string
[0-9]+ - Atleast 1 number
/ - character literal
$ - end of string
These lines are expanding your beginning and ending numbers:
range="{${element%/*}..${element##*/}}"
mynumbers=( $(eval "echo $range") )
This is maybe more complicated than it needs to be as most people try to avoid eval in general for security reasons. I'm leveraging bash's brace expansion. If you run echo {5..9}, it will output 5 6 7 8 9. This does not trigger with variables, so I cheated and used eval.
This line is checking if we are dealing with an integer:
[ $element -eq $element ] 2>> /dev/null
This works by running an integer -eq (equals) comparison on the variable against itself. This will actually fail and throw an error message on anything but an integer. This is not the way it was designed to be used which is why we discard all the error messages (2>> /dev/null).
This is a nice succinct script, but is using some unconventional practices. A longer more verbose version may be better for a beginner.
You can use regular expressions to match elements that are nothing but digits, or digits/digits, and assume everything else is a string:
#!/bin/bash
myarr=(2301/2320 "Time Lifeline" 2311 7650/7670 232)
declare -a mynumbers mystrarr myintarr
for elem in "${myarr[#]}"; do
if [[ $elem =~ ^([0-9]+)/([0-9]+)$ ]]; then
mynumbers+=($(seq ${BASH_REMATCH[1]} ${BASH_REMATCH[2]}))
elif [[ $elem =~ ^[0-9]+$ ]]; then
myintarr+=($elem)
else
mystrarr+=("$elem")
fi
done
echo mynumbers is "${mynumbers[#]}"
echo myintarr is "${myintarr[#]}"
echo mystrarr is "${mystrarr[*]}"
Jason explained a lot in his (very similar; there's only so many obvious ways to do this) answer, so to expand on where ours are different:
We both use regular expressions to match the integer/integer case, but he then goes on to extract the two numbers using parameter expansion with pattern removal options, while mine captures the two integers in the regular expression, and uses the BASH_REMATCH array to access their values as well as the seq command to generate the numbers between the two.
I have this variable:
A="Some variable has value abc.123"
I need to extract this value i.e abc.123. Is this possible in bash?
Simplest is
echo "$A" | awk '{print $NF}'
Edit: explanation of how this works...
awk breaks the input into different fields, using whitespace as the separator by default. Hardcoding 5 in place of NF prints out the 5th field in the input:
echo "$A" | awk '{print $5}'
NF is a built-in awk variable that gives the total number of fields in the current record. The following returns the number 5 because there are 5 fields in the string "Some variable has value abc.123":
echo "$A" | awk '{print NF}'
Combining $ with NF outputs the last field in the string, no matter how many fields your string contains.
Yes; this:
A="Some variable has value abc.123"
echo "${A##* }"
will print this:
abc.123
(The ${parameter##word} notation is explained in ยง3.5.3 "Shell Parameter Expansion" of the Bash Reference Manual.)
Some examples using parameter expansion
A="Some variable has value abc.123"
echo "${A##* }"
abc.123
Longest match on " " space
echo "${A% *}"
Some variable has value
Longest match on . dot
echo "${A%.*}"
Some variable has value abc
Shortest match on " " space
echo "${A%% *}"
some
Read more Shell-Parameter-Expansion
The documentation is a bit painful to read, so I've summarised it in a simpler way.
Note that the '*' needs to swap places with the ' ' depending on whether you use # or %. (The * is just a wildcard, so you may need to take off your "regex hat" while reading.)
${A% *} - remove shortest trailing * (strip the last word)
${A%% *} - remove longest trailing * (strip the last words)
${A#* } - remove shortest leading * (strip the first word)
${A##* } - remove longest leading * (strip the first words)
Of course a "word" here may contain any character that isn't a literal space.
You might commonly use this syntax to trim filenames:
${A##*/} removes all containing folders, if any, from the start of the path, e.g.
/usr/bin/git -> git
/usr/bin/ -> (empty string)
${A%/*} removes the last file/folder/trailing slash, if any, from the end:
/usr/bin/git -> /usr/bin
/usr/bin/ -> /usr/bin
${A%.*} removes the last extension, if any (just be wary of things like my.path/noext):
archive.tar.gz -> archive.tar
How do you know where the value begins? If it's always the 5th and 6th words, you could use e.g.:
B=$(echo "$A" | cut -d ' ' -f 5-)
This uses the cut command to slice out part of the line, using a simple space as the word delimiter.
As pointed out by Zedfoxus here. A very clean method that works on all Unix-based systems. Besides, you don't need to know the exact position of the substring.
A="Some variable has value abc.123"
echo "$A" | rev | cut -d ' ' -f 1 | rev
# abc.123
More ways to do this:
(Run each of these commands in your terminal to test this live.)
For all answers below, start by typing this in your terminal:
A="Some variable has value abc.123"
The array example (#3 below) is a really useful pattern, and depending on what you are trying to do, sometimes the best.
1. with awk, as the main answer shows
echo "$A" | awk '{print $NF}'
2. with grep:
echo "$A" | grep -o '[^ ]*$'
the -o says to only retain the matching portion of the string
the [^ ] part says "don't match spaces"; ie: "not the space char"
the * means: "match 0 or more instances of the preceding match pattern (which is [^ ]), and the $ means "match the end of the line." So, this matches the last word after the last space through to the end of the line; ie: abc.123 in this case.
3. via regular bash "indexed" arrays and array indexing
Convert A to an array, with elements being separated by the default IFS (Internal Field Separator) char, which is space:
Option 1 (will "break in mysterious ways", as #tripleee put it in a comment here, if the string stored in the A variable contains certain special shell characters, so Option 2 below is recommended instead!):
# Capture space-separated words as separate elements in array A_array
A_array=($A)
Option 2 [RECOMMENDED!]. Use the read command, as I explain in my answer here, and as is recommended by the bash shellcheck static code analyzer tool for shell scripts, in ShellCheck rule SC2206, here.
# Capture space-separated words as separate elements in array A_array, using
# a "herestring".
# See my answer here: https://stackoverflow.com/a/71575442/4561887
IFS=" " read -r -d '' -a A_array <<< "$A"
Then, print only the last elment in the array:
# Print only the last element via bash array right-hand-side indexing syntax
echo "${A_array[-1]}" # last element only
Output:
abc.123
Going further:
What makes this pattern so useful too is that it allows you to easily do the opposite too!: obtain all words except the last one, like this:
array_len="${#A_array[#]}"
array_len_minus_one=$((array_len - 1))
echo "${A_array[#]:0:$array_len_minus_one}"
Output:
Some variable has value
For more on the ${array[#]:start:length} array slicing syntax above, see my answer here: Unix & Linux: Bash: slice of positional parameters, and for more info. on the bash "Arithmetic Expansion" syntax, see here:
https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Arithmetic-Expansion
https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Shell-Arithmetic
You can use a Bash regex:
A="Some variable has value abc.123"
[[ $A =~ [[:blank:]]([^[:blank:]]+)$ ]] && echo "${BASH_REMATCH[1]}" || echo "no match"
Prints:
abc.123
That works with any [:blank:] delimiter in the current local (Usually [ \t]). If you want to be more specific:
A="Some variable has value abc.123"
pat='[ ]([^ ]+)$'
[[ $A =~ $pat ]] && echo "${BASH_REMATCH[1]}" || echo "no match"
echo "Some variable has value abc.123"| perl -nE'say $1 if /(\S+)$/'
Following output consisting of several devices needs to be parsed:
0 interface=ether1 address=172.16.127.2 address4=172.16.127.2
address6=fe80::ce2d:e0ff:fe00:05 mac-address=CC:2D:E0:00:00:08
identity="myrouter1" platform="MikroTik" version="6.43.8 (stable)"
1 interface=ether2 address=10.5.44.100 address4=10.5.44.100
address6=fe80::ce2d:e0ff:fe00:07 mac-address=CC:2D:E0:00:00:05
identity="myrouter4" platform="MikroTik" version="6.43.8 (stable)"
3 interface=ether4 address=fe80::ba69:f4ff:fe00:0017
address6=fe80::ba69:f4ff:fe00:0017 mac-address=B8:69:F4:00:00:07
identity="myrouter2" platform="MikroTik" version="6.43.8 (stable)"
...
10 interface=ether5 address=10.26.51.24 address4=10.26.51.24
address6=fe80::ba69:f4ff:fe00:0039 mac-address=B8:69:F4:00:00:04
identity="myrouter3" platform="MikroTik" version="6.43.8 (stable)"
11 interface=ether3 address=10.26.51.100 address4=10.26.51.100
address6=fe80::ce2d:e0ff:fe00:f00 mac-address=CC:2D:E0:00:00:09
identity="myrouter5" platform="MikroTik" version="6.43.8 (stable)"
edit: for ease of things I shortened and anonymized the output, first block has 7 lines, second block has 5 lines, third block has 7 lines, fourth block 4 lines, so the number of lines is inconsistent.
Basically its the output from a Mikrotik device: "/ip neighbor print detail"
Optimal would be to access every device(=number) on its own, then further access all setting=value (of one device) seperately to finally access settings like $device[0][identity] or similar.
I tried to set IFS='\d{1,2} ' but seems IFS only works for single character seperation.
Looking on the web I didn't find a way to accomplish this, am I looking for the wrong way and there is another way to solve this?
Thanks in advance!
edit: Found this solution Split file by multiple line breaks which helped me to get:
devices=()
COUNT=0;
while read LINE
do
[ "$LINE" ] && devices[$COUNT]+="$LINE " || { (( ++COUNT )); }
done < devices.txt
then i could use #Kamil's solution to easily access values.
While your precise output format is a bit unclear, bash offers an efficient way to parse the data making use of process substitution. Similar to command substitution, process substitution allows redirecting the output of commands to stdin. This allows you to read the result of a set of commands that reformat your mikrotik file into a single line for each device.
While there are a number of ways to do it, one of the ways to handle the multiple gymnastics needed to reformat the multi-line information for each device into a single line is by using tr and sed. tr to first replace each '\n' with an '_' (or pick your favorite character not used elsewhere), and then again to "squeeze" the leading spaces to a single space (technically not required, but for completeness). After replacing the '\n' with '_' and squeezing spaces, you simply use two sed expressions to change the "__" (resulting from the blank line) back into a '\n' and then to remove all '_'.
With that you can read your device number n and the remainder of the line holing your setting=value pairs. To ease locating your "identity=" line, simply converting the line into an array and looping using parameter expansions (for substring removal), you can save and store the "identity" value as id (trimming the double-quotes is left to you)
Now it is simply a matter of outputting the value (or doing whatever you wish with them). While you can loop again and output the array values, it is just a easy to pass the intentionally unquoted line to printf and let the printf-trick handle separating the setting=value pairs for output. Lastly, you form your $device[0][identity] identifier and output as the final line in the device block.
Putting it altogether, you could do something like the following:
#!/bin/bash
id=
while read n line; do ## read each line from process substitution
a=( $line ) ## split line into array
for i in ${a[#]}; do ## search array, set id
[ "${i%=*}" = "identity" ] && id="${i##*=}"
done
echo "device=$n" ## output device=
printf " %s\n" ${line[#]} ## output setting=value (unquoted on purpose)
printf " \$device[%s][%s]\n" "$n" "$id" ## $device[0][identity]
done < <(tr '\n' '_' < "$1" | tr -s ' ' | sed -e 's/__/\n/g' -e 's/_//g')
Example Use/Output
Note, the script takes the filename to parse as the first input.
$ bash mikrotik_parse.sh mikrotik
device=0
interface=ether1
address=172.16.127.2
address4=172.16.127.2
address6=fe80::ce2d:e0ff:fe00:05
mac-address=CC:2D:E0:00:00:08
identity="myrouter1"
platform="MikroTik"
version="6.43.8
(stable)"
$device[0]["myrouter1"]
device=1
interface=ether2
address=10.5.44.100
address4=10.5.44.100
address6=fe80::ce2d:e0ff:fe00:07
mac-address=CC:2D:E0:00:00:05
identity="myrouter4"
platform="MikroTik"
version="6.43.8
(stable)"
$device[1]["myrouter4"]
device=3
interface=ether4
address=fe80::ba69:f4ff:fe00:0017
address6=fe80::ba69:f4ff:fe00:0017
mac-address=B8:69:F4:00:00:07
identity="myrouter2"
platform="MikroTik"
version="6.43.8
(stable)"
$device[3]["myrouter2"]
Look things over and let me know if you have further questions. As mentioned at the beginning, you haven't defined an explicit output format you are looking for, but gleaning what information was in the question, this should be close.
I think you're on the right track with IFS.
Try piping IFS=$'\n\n' (to break apart the line groups by interface) through cut (to extract the specific field(s) you want for each interface).
Bash likes single long rows with delimter separated values. So first we need to convert your file to such format.
Below I read 4 lines at a time from input. I notices that the output spans over 4 lines only - I just concatenate the 4 lines and act as if it is a single line.
while
IFS= read -r line1 &&
IFS= read -r line2 &&
IFS= read -r line3 &&
IFS= read -r line4 &&
line="$line1 $line2 $line3 $line4"
do
if [ -n "$line4" ]; then
echo "ERR: 4th line should be empt - $line4 !" >&2
exit 4
fi
if ! num=$(printf "%d" ${line:0:3}); then
echo "ERR: reading number" >&2
exit 1
fi
line=${line:3}
# bash variables can't have `-`
line=${line/mac-address=/mac_address=}
# unsafe magic
vars=(interface address address4
address6 mac_address identity platform version)
for v in "${vars[#]}"; do
unset "$v"
if ! <<<"$line" grep -q "$v="; then
echo "ERR: line does not have $v= part!" >&2
exit 1
fi
done
# eval call
if ! eval "$line"; then
echo "ERR: eval line=$line" >&2
exit 1
fi
for v in "${vars[#]}"; do
if [ -z "${!v}" ]; then
echo "ERR: variable $v was not set in eval!" >&2
exit 1;
fi
done
echo "$num: $interface $address $address4 $address6 $mac_address $identity $platform $version"
done < file
then I retrieve the leading number from the line, which I suspect was printed with printf "%3d" so I just slice the line ${line:0:3}
for the rest of the line I indent to use eval. In this case I trust upstream, but I try to assert some cases (variable not defined in the line, some syntax error and similar)
then the magic eval "$line" happens, which assigns all the variables in my shell
after that I can use variables from the line like normal variables
live example at tutorialspoint
Eval command and security issues
Good day.
Everyday i receive a list of numbers like the example below:
11986542586
34988745236
2274563215
4532146587
11987455478
3652147859
As you can see some of them have a 9(11 digits total) in as the third digit and some dont(10 digits total, that`s because the ones with an extra 9 are the new Brazilian mobile number format and the ones without it are in the old format.
The thing is that i have to use the numbers in both formats as a parameter for another script and i usually have do this by hand.
I am trying to create a script that reads the length of a mobile number and check it`s and add or remove the "9" of a number or string if the digits condition is met and save it in a separate file condition is met.
So far i am only able to check its length but i don`t know how to add or remove the "9" in the third digit.
#!/bin/bash
Numbers_file="/FILES/dir/dir2/Numbers_File.txt"
while read Numbers
do
LEN=${#Numbers}
if [ $LEN -eq "11" ]; then
echo "lenght = "$LEN
elif [ $LEN -eq "10" ];then
echo "lenght = "$LEN
else
echo "error"
fi
done < $Numbers_file
You can delete the third character of any string with sed as follows:
sed 's/.//3'
Example:
echo "11986542586" | sed 's/.//3'
1186542586
To add a 9 in the third character:
echo "2274563215" | sed 's/./&9/3'
22794563215
If you are absolutely sure about the occurrence happening only at the third position, you can use an awk statement as below,
awk 'substr($0,3,1)=="9"{$0=substr($0,1,2)substr($0,4,length($0))}1' file
1186542586
3488745236
2274563215
4532146587
1187455478
3652147859
Using the POSIX compliant substr() function, process only the lines having 9 at the 3rd position and move around the record not considering that digit alone.
substr(s, m[, n ])
Return the at most n-character substring of s that begins at position m, numbering from 1. If n is omitted, or if n specifies more characters than are left in the string, the length of the substring shall be limited by the length of the string s
There are lots of text manipulation tools that will do this, but the lightest weight is probably cut because this is all it does.
cut only supports a single range but does have an invert function so cut -c4 would give you just the 4th character, but add in --complement and you get everything but character 4.
echo 1234567890 | cut -c4 --complement
12356789
For example:
((
extract everything here, ignore the rest
))
I know how to ignore everything within, but I don't know how to do the opposite. Basically, it'll be a file and it needs to extract the data between the two points and then output it to another file. I've tried countless approaches, and all seem to tell me the indentation I'm stating doesn't exist in the file, when it does.
If somebody could point me in the right direction, I'd be grateful.
If your data are "line oriented", so the marker is alone (as in the example), you can try some of the following:
function getdata() {
cat - <<EOF
before
((
extract everything here, ignore the rest
someother text
))
after
EOF
}
echo "sed - with two seds"
getdata | sed -n '/((/,/))/p' | sed '1d;$d'
echo "Another sed solution"
getdata | sed -n '1,/((/d; /))/,$d;p'
echo "With GNU sed"
getdata | gsed -n '/((/{:a;n;/))/b;p;ba}'
echo "With perl"
getdata | perl -0777 -pe "s/.*\(\(\s*\\n(.*)?\)\).*/\$1/s"
Ps: yes, its looks like a dance of crazy toothpicks
Assuming you want to extract the string inside (( and )):
VAR="abc((def))ghi"
echo "$VAR"
VAR=${VAR##*((}
VAR=${VAR%%))*}
echo "$VAR"
## cuts away the longest string from the beginning; # cuts away the shortest string from the beginning; %% cuts away the longest string at the end; % cuts away the shortes string at the end
The file :
$ cat /tmp/l
((
extract everything here, ignore the rest
someother text
))
The script
$ awk '$1=="((" {p=1;next} $1=="))" {p=o;next} p' /tmp/l
extract everything here, ignore the rest
someother text
sed -n '/^((/,/^))/ { /^((/b; /^))/b; p }'
Brief explanation:
/^((/,/^))/: range addressing (inclusive)
{ /^((/b; /^))/b; p }: sequence of 3 commands
1. skip line with ^((
2. skip line with ^))
3. print
The line skipping is required to make the range selection exclusive.