Questions about shell scripts, executable files that are interpreted by a shell (bash, zsh, etc.).

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0answers
14 views

Want to write a unix script to compare two files with multiple columns

Need to make a script in unix .I have 2 files with same structure with pipe as a delimiter. Now first i want to check if column1(eid)-->file1 is present in column1(eid)-->file2,if so then it will ...
1
vote
2answers
20 views

How to can I make Filename Sequencing with the help of Loops

my intention is to keep the code as simple as possible.Here there are 5 files namely A_1.CSV, A_2.CSV, A_3.CSV, A_4.CSV, A_5.CSV The below code retrieves the first row in a CSV file. Code : ...
0
votes
1answer
21 views

Is `grep -P` (Perl/Python regex) portable on most linux distributions

I prefer (Perl/Python Compatible Regular Expressions) regular expressions. man grep: ...., but only work if pcre is available in the system Is this supported on the most common linux ...
-1
votes
0answers
24 views

problem in AWK with Shell scripting

Aim : I have 5 .CSV files namely 1. A.CSV 2. B.CSV 3. C.CSV 4. D.CSV 5. E.CSV I just want to copy the header column names from each file and place to another file named Header.csv . Code : ...
-4
votes
1answer
30 views

I need some help writing a script in unix [on hold]

I want to make a script in unix .I have 2 files with same structure with pipe as a delimiter. Now first i want to check if column1(eid)-->file1 is present in column1(eid)-->file2,if so then it will ...
0
votes
1answer
31 views

Creating multiple input files by using sed in a for loop

I am a newbie and wasted a lot of time on this so any help is greatly appreciated. Suppose I have a simple Mathematica script file named "a.m" which contains the parameter 'a' with no assigned value: ...
1
vote
2answers
33 views

How to grep over a variable

I have a scenario like VAR = `Some command brings the file path name and assigns it to VAR` For example VAR can have value like /root/user/samp.txt I want to grep command like grep HI $VAR ...
0
votes
1answer
19 views

Processing output from an sqlite db into a ksh array with spaces [on hold]

I am querying an SQLite3 database like so: input=$(-separator "," "SELECT field1,field2,field3 FROM table1") and get this result: Red,Yellow is a color,Blue I need to insert this into an array, ...
1
vote
1answer
27 views

remove lines where a field's value is less than or equal to 3 - sed or awk?

I need to remove every line that has a value of 2 or less in the 8th field (column). My data looks like this: 12-31 Airport 189 379 41 49.70946503 -124.91377258 2 2880 30.8 01-01 ...
0
votes
0answers
13 views

Debian start script strips -f from command

I wrote the start script at the bottom of this question to try to get one of my devices to automatically create several remote forwarded ports with my VPS upon boot. (I've stripped the LSB tags to ...
2
votes
2answers
42 views

Copy files to a destination folder only if the files already exist. but the source files have a different file extension

Copy files to a destination folder only if the files already exist. but the source files have a different file extension. i.e I have a backup of some files with ".desktop.in" extension and I want to ...
3
votes
1answer
30 views

Running a script during booting/startup; initi.d vs @reboot

I am currently trying to understand the difference between init.d and @reboot for running a script at startup/booting of the system. The use of @reboot (this method was mentioned in this forum by ...
1
vote
1answer
30 views

Specify the type of field to modify in a file

I have a list of clients, "code", "name", "location", "etc" and I want to make a function that asks the employee to give the client's code and then the field he/she wants to change. For example, ...
1
vote
0answers
30 views

Text User Interface

I have been working on a shell script, and was wondering if I can put up a text user interface for the shell script. After some searching, I see few people suggest using "ncurses/curses". However the ...
1
vote
1answer
57 views

Shell script `rm -r`: Redirect write-protected prompt and answer “n”

I have a few lines in a shell script whose function is to iterate through directories, match some names, and delete them. Some areas of the file system are write protected and I would like to leave ...
2
votes
3answers
45 views

Calculate date difference between Last modified date of a file and NOW using shell script

I am trying to calculate the time elapsed since the log file was last updated. I guess following commands will be used lastUpdate=$(date -r myLogFile.log) now=$(date) How can I subtract them and ...
3
votes
5answers
158 views

Pick the latest file based upon the sequence number given in the file name

I have a requirement, I have few files in a directory, I need to pick the oldest one for processing. For Exp: I have below files in /tmp directory: Sample_0000237826-001_xyz.dat ...
1
vote
1answer
19 views

Record commands only to file

How can I record commands only to a file? I imagine something like the script command, but not recording prompts or the OS response, just the entered commands followed by a line feed. I want to ...
1
vote
1answer
42 views

loop through multiple folders and perform commands then write to file

I have 10 folders that I want to loop through while executing the following command: awk 'FNR > 1' *.csv | sort -sk 1,2 | sort -sk 3,3 > ${f}_appended.dat With a for loop wrapper, like ...
-1
votes
1answer
41 views

Can you please tell me what is wrong in below script?

script : it is giving below error. please help me. basically i need to get email when memory exceeds some limit. error : ./vamsitest.sh: line 10: [: missing `]'   #! /bin/bash # Total memory ...
0
votes
2answers
26 views

provide password for script begin called inside another script [duplicate]

I have written a shell script which in turn calls another script, but the second one prompts for password. I want to supply the password and pass the prompt without user begin notified. Here is my ...
-1
votes
0answers
48 views

I'd like to write shell script to connect to database and delete the records automatically [on hold]

Can you please help me to write shell script which should delete records from my delete query and same will be appear in log file by saying record has been deleted. Also once this is done, it should ...
3
votes
1answer
46 views

Edit a file via a script yet maintain the osx tags

On OSX you can have tags which allows you to identify different categories of files. Here are two text files with different tags when viewed in Finder: I have a large number of these files and have ...
0
votes
1answer
13 views

Files missing after using mv and parameter substitution in a loop

Related questions to missing files after mv don't appear to answer my question. The following commands were run within the working directory where the files are located, resulting in missing files. ...
0
votes
2answers
43 views

Gzip file but excluding some directories|files and also append current date

I'm looking for a way to create a .tar.gz file from a directory but I have some doubts. I'm know that the command for create the file is: tar -zcvf /path/to/compressed/file.tar.gz /path/to/compress ...
0
votes
0answers
14 views

single jq command with multiple output possible?

I have json log file test.log {"type":"1","fname":"AAA","lname":"bbb" } {"type":"2","state":"gujarat" } {"type":"3","city":"ahmedabad" } {"type":"3","city":"rajkot" } ...
4
votes
1answer
148 views

Can I refer to a global variable even if a locally scoped one exists with the same name?

If I have a variable x total=3 and then a function function A () { local -i total=0 } Is there any way I can update the 'global' total variable total from within function A ?
1
vote
2answers
70 views

use “read” command to pass lines as positional parameters to a shell script

The following file runs, but not doing anything, yet it does not error.... while read dates; do ./avg_hrly_all_final.sh ${dates}; done < ./dates_all.csv I have a list of dates in ...
0
votes
2answers
29 views

I want to print the value from csv file dynamically

I want to print the values from properties file dynamically I am using below code but getting wrong output. testProperty.properties edmcws,edmbws,edmwt Code ...
3
votes
3answers
91 views

spawn - command not found!

I am using Mac OS X 10.9.4, following is my script to copy files from local machine to different host #!/bin/bash #!/usr/bin/expect echo "I will fail if you give junk values!!" echo " " echo "Enter ...
4
votes
2answers
70 views

Use lines in a file to produce string and file name

I have a file, foo.txt, that has a folder name on each line: folder_1 folder_2 folder_3 And I'd like to do something like this: cat foo.txt | xargs -I {} echo 'function {}() { return stuff; }' ...
2
votes
3answers
65 views

How do I use inserted values using getopts

I have this bash code combined with getopts and if I understood getopts correctly OPTIND contains the index of the next command line option and all the command line options provided to shell script ...
2
votes
1answer
43 views

attempting to put dynamic input data in a variable via cat method

I'm attempting to write a bash script that should be able to collect data from ttyS0 and put in a variable. I need to talk with a device on the serial line, that is a module able to receive AT ...
1
vote
3answers
58 views

Traverse all subdirectories in and do something in Unix shell script

I am new to bash scripting. I am working on a shell script and got stuck from last 3 days. I want my shell script to visit all subdirectories in a main directory. Do something in directories, sent ...
1
vote
2answers
44 views

Extracting numbers with a decimal point from ls output in Bash

I would like to extract the numeric part of the file names that begin with "hsli" and end with ".h5" in Bash on Ubuntu 14.04.1 64-bit LTS. My ls -l hsli* output is as follows: -rwxrwxrwx 1 ongun ...
0
votes
1answer
16 views

how to find the files in a directory with Prefix__date_030000_1.txt?

how to find the files in a directory with Prefix__date_030000_Suffix here Prefix is the Actual file name and format of the date is date +%Y%m%d and Suffix is the '.txt' and the 030000 number will ...
0
votes
1answer
23 views

Run windows local program from remote linux

I'm trying to run a python script on a remote linux machine accessed by SSH from my local Windows machine. The script contains a loop where for all files in a directory it's going to go to a certain ...
1
vote
1answer
23 views

Handle compress command error messages on AIX

I am working on production issue and unable to reproduce error message for compress command. Current Solution We have case-esac block in shell wrapper that handles messages as follows; case "$MSG" ...
-3
votes
1answer
38 views

find all .sh files then copy to <date>scriptbackup

Locate all the .sh scripts you have created in your Linux installation (searching recursively if needed – excluding existing backup folders) It will then copy them all into a folder called ...
-2
votes
0answers
19 views

shell script to know the status of a node's application, whether it is up or down [closed]

I want to know the status of an application and application server which I cant get directly. It is like connecting to a server lets say 'A' and that server has many nodes say A1.A2,A3 and in that ...
1
vote
1answer
48 views

Print lines between two patterns matching a condition in awk

How can I print lines between two patterns which meet a certain condition? For instance for an input file partially containing the following: Time %MEM %CPU %SWAP 00:05:02 7.3 ...
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votes
0answers
29 views

Count how many times a word occurs in a txt file with awk

Basically i'm trying to count all instances of certain words that occur in a text file then printing the result. It has to be in done using awk. Im not really sure where to start. Any suggestions?
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votes
0answers
28 views

Random password generator [closed]

Make a random password generator: read 3 to 5 random lines from /usr/dict/words and assemble them together to form a random password. the command should takes an optional minimum size argument that ...
1
vote
1answer
48 views

getopts passing value of declared parameter to function

I have function port.sh as stand alone script and i'm wondering if is possible to put this function in the same script where getopts is and pass value of OPT_B into function and get output of it? ...
0
votes
2answers
41 views

How to call on 3 scripts inside a shell script

I am battling to run a shell script which has 3 scripts which it needs to call and execute one after each other as soon as the execution completes successfully (error: gzip:.gz: unexpected end of ...
0
votes
3answers
49 views

Parent script continues when child exits with non-zero exit code [closed]

I have a script that calls another script. When the child script fails, I'd like the parent to fail as well. In the child script child_1.sh, I have something like this: if [ $SOME_BAD_CONDITION ] ; ...
0
votes
2answers
63 views

Read line from a file

Hello how can i read each line from a file and compare it with other file... Actually that file should be taken from command line.... please help me out if [[-f $@ ]]; then for "$line" in $@; ...
4
votes
2answers
240 views

Delete files older than specific file

I need to delete from a folder all files older than a specific file. Running bash on CentOS 7. I have a solution for this, but I think there should be a more elegant way do it: ...
1
vote
2answers
47 views

print the output of 2 commands in 1 file on the same line

Thanks for looking at this. I have a possible simple question, but I wasn't able to find any help so far on the internet. I have a script that has mainly 2 commands that process output. But both ...
1
vote
2answers
70 views

Search for matching files with wildcards without using find in a bash script

For an assignment, I'm supposed to write a bash script that can act as a very basic find, but without actually using the find command. For example, if I put in this input: my_find ~/homedir/ -name ...