Programming :: Bash Variable Parsing / Extract And Put Into Variables Each Combination Of F1 And F2 In A Loop?
Oct 14, 2010
I have a bash variable where the content looks like this where ;f1; and ;f2; are delimiters:
;f1;field1value1;f2;field2 value1 ;f1;field1value2;f2;field2 value2 ;f1;field1value3;f2;field2 value3
So what I need is to extract and put into variables each combination of f1 and f2 in a loop to something like that:
#first pass of the loop I need:
f1=field1value1
f2=field2 value1
#second pass of the loop I need:
f1=field1value2
f2=field2 value2
# third pass of the loop I need:
f1=field1value3
f2=field2 value3
I'm trying to read content of file to variable and use this variable in for loop. The problem is, when I have c++ comment style in file - /*. Spaces in line are also interpreted as separated lines.
For example:
Code:
Changing $files to "$files" eliminate these problems but causes that whole content of variable is treated as one string (one execution of loop).
2. for I in 1 2 3 4 5 6 7 8 9 10; do echo $I; done|
3. for I in $(seq 1 10); do echo $I; done|
4. for ((I=1; I <= 10 ; I++)); do echo $I; done
I have a script which uses the 1st form of for loop. I'm trying to modify it to use a variable instead of a static hard-coded value in the section that controls the looping.of the for loop.
I've tried all different ways of quoting and escaping the variable, and the problem is that the quoting chars and escape char are being translated and passed into the loop along with the value stored in the variable.
For example, to change the start value of 1 to whatever value I want passed in through a variable:
Change:
I have tried: {{$a}..10} and {`$a`..10}, to have the variable evaluated first.
I have tried using the eval() function.
I have tried single and double quotes and the backslash escape character.
Nothing I've tried works. It's probably a syntax error.
As you can see on the output of the script, the two 'testing echoes' I do at the end don't print anything.That's the point, I do NEED this array further in my script.I'd understand my "param" var is local to the for, but is the other one too ? I tried to use "declare -a file" before the for, but i get same exact result !
I've searched online and found many examples using getopts, but nothing that clearly explains it use, nor any examples of what I'm trying to do. I have a script named "process". It can take from 0 to 3 different options. I'd like to be able to handle these options regardless of the order that they are entered.
Syntax: process [-v] [-d #] [-h|-?] [string] -v = verbose mode on -d # = how deep to do the process, expecting a number parameter -h or -? = show command usage string = only process lines containing the specified string
I'm reading "OReilly Learning Perl 5th Edition", and there are such words:Code:You can use an array element like $fred[2] in every place? where you could use any other scalavariable like $fred.At the bottom of the page, it explains the ? like this:Code:The most notable exception is that the control variable of a foreach loop, which you?ll see later in this chapter, must be a simple scalar.Since Perl has the save-and-restore mechanism for the control variable, why an array element can't be used as the control variable
Is there a way to process individual characters one-by-one from a text file in Bash, or is that hoping for a little too much from this lovable old clunker?
PI'm trying to write a script to list all open ports in the MINIUNPND chain in iptables and use the procotol, port and destination ip to open ports on another router using upnpc.Here is the output of iptables -L MINIUPNPD
No matter what i do i cant seem to remove the first 4 characters from the MYPROT array to leave only the digits. Also i cant seem to read the array back???
I thought it would simply be a loop reading each line and passing the fields in variables, executing upnpc commands i need then moving to the next line of the file until it reached the EOF.
Now in my bash script, I want to get the output /home/user instead of $HOME once read. So far, I have managed to get the $HOME variable but I can't get it to echo the variable. All I get is the output $HOME.
I need to rename the resulted searched files from a loopI have the following code:
find . -name DOC* | while read i do find $i -type f -name '*.txt' done
basically, I am searching for all txt files inside any folder starting with DOC name.this code is working fine with me.I need to rename those .txt files to .txtOLDOS: Ubuntu 10.4Bash shell
I'm trying to write a bash script and I'm having trouble with it.I have a list of DNS entires from a file called zoneExport.txt.Than I want to parse a log file to see if that DNS entry has been queried for. So I'm running a grep command and trying to save it into a variable. What I'm looking for is a variable ($varGrepQ) that has the number of matches for the grep query. I will then run this through an if statement and do some things from there..
But my problem right now is with this grep query. It keeps outputting '0' even when I know there are records in that file and when I run the same query on the command line I get the actual count. My thought is that the $record variable is not passing right.
If I read in variables entered by the user, how can I check to make sure the correct number of variables were entered? For example, after reading in a data file and making it into an array, I have:echo "To check the data, enter the first element number, last element number and step size as x y z:"read x y z.It then goes on to start a loop, but what I would like now (before the loop) is a check to see if three variables have been entered, before the rest of the script continues.
I've tried specifying the variables as $1, $2 and $3, but if I echo $#, the value comes out as zero, so it's obviously not working.
I'm writing a mass snmp toner check which polls any toners available to be snmp polled, however when using a loop statement I get the results on different lines; which sounds good, however the tool I use to check with (nagios) ignores the new lines.
Is there any way I can get the output on one line? Also, I need to raise a fault if any of the toners are below a specific level (with nagios you raise faults with the exit code) - any way I can do this without exiting the loop. Code below with bits and bobs commented out.
The script that Iam trying to write is running a for loop and reading line by line from a text file. inside this for loop i would like to execute update SQL statement .
a pesudo code is Quote: `$ISQL -U $username -P $Password -D $Dbname -I $INTERFACE <<QRY for id in $idlist #idlist iam reading from a file
PU12829,24869;PD15733,24869;PD15733,19785;PD12829,19785;PD12829,24869; PU4599,20915;PD9924,20915;PD9924,18898;PD4599,18898;PD4599,20915; PU12829,24869;PD15733,24869;PD15733,19785;PD12829,19785;PD12829,24869; PU4599,20915;PD9924,20915;PD9924,18898;PD4599,18898;PD4599,20915; PU1723,3423; #this line is ignored to short
[Code]...
What I'm trying to do is while true, cut each line from file that begins with PU and thats longer than 12 characters and write to a increasing numbered file for each line. Stating with object1 etc.
So I need to write a bash script that can read lines and column 3 from a file. It needs to start on line 16 and read every 20th line starting from there. But the value that it reads needs to be checked, should it be too great I need it to shut the program down.I'm pretty new to bash, but my ultimate goal is being able to safely run a program on a GPU for an extended period of time with out worrying about it overheating. I have a command that outputs information from the GPU every second, and I can save this to a file. So all I really need is something to read and check that file, I played around a bit with the awk command and can't get it to work within my for loop with dynamic variable.
I need to know how to assign a result from a select. I am clueless on the sytax. I am trying this in bash. Maybe I am not assigning the array right. It gives me the whole row in the echo instead of just field a. How do I get fieldA = a in the select. Note script was stripped for security on database info but the syntax is same.
Code:
#!/bin/sh results="$(mysql --user ${DB_USER} -p${DB_PWD} ${DB_NAME} -Bse 'select a,b,c,d from tblMytable')" for rows in "${results[@]}" do fieldA=${rows[0]}; echo ${fieldA}; done
How do I get this loop to stop on each increment? This script does work but I would like it to stop at each increment, remember what the value of $n is, then continue until it gets to 7. I have worked so hard on this. My brain is hurting now.
I have a problem with snmp answers being empty or having spaces.
What I already have:
#get all interface indexes (if you wonder - I'm working for a cable company and different cablemodems have different number and types of interfaces):
The problem is the physical address which is sometimes empty and the description which has spaces. So I'm doing 2 snmpgets which is slower than 1 snmpget (sometimes I have up to 18 interfaces).
I'm trying to explain it a bit simpler.
Interface 5 gives me back the following lines:
Ethernet CPE Interface
Now the first line should go into variable ifadm, 2nd line should go into variable ifoper, 3rd line should go into variable ifspeed, 4th line should go into variable iftype, 5th line (which is empty) should go into variable ifphys and finally 6th line (which has spaces) should go into variable ifdescr
mkvmerge -o <filename without extension>_TV.mkv -S <filename> && mkvextract tracks <filename> 3:<filename without extension>.*** && perl /home/brian/Desktop/ass2srt.pl <filename without extension>.*** && rm <filename without extension>.***
Doing these commands for multiple command line file inputs is the goal. So I can just type ./script.sh *.mkv in my terminal.This is what I have so far, but it doesn't work whatsoever.
Just a simple BASH for loop to read the file path from a text file (clean.txt) echo the variable for debug purposes, and scp it to a server I have using port 50 for SSH.
I've already formatted the entries in clean.txt to handle spaces correctly, using sed replacement.
Example from the clean.txt file:
Code: /MP3/NAS000000001/Barenaked Ladies/Barenaked Ladies - Barenaked For The Holidays/20 Auld Lang Syne.mp3 /MP3/NAS000000001/Barenaked Ladies/Barenaked Ladies - Barenaked For The Holidays/14 Deck the Stills.mp3