Questions about bash only, as opposed to other Bourne/POSIX shells. For all Bourne/POSIX-style shells, use the /shell tag instead.

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6
votes
4answers
913 views

Find files alphabetically before a given string

If I have a directory full of files and sub directories. What is the best way to list just the regular files which fall alphabetically before a given string? Currently the best I can do using bash is ...
0
votes
0answers
2k views

bad magic number

I have a script which I need to execute. The script file is push.sh. Below are the commands that I am using: dragan@dragan-Lenovo-G570:~/liquibase/liquibase$ chmod +x push.sh ...
2
votes
1answer
392 views

The meaning of '-' and '+' symbol when background processes are finished?

When I am running background processes like(I have 9 files suffixed by phastcon): for i in *.phastcon; do cut -f 2 $i >$i.value & done After kicking the "Enter", I get the output in terminal ...
31
votes
4answers
4k views

Using '.' to execute files in bash

What's the difference between executing a script like this: ./test.sh and executing a script like this: . test.sh? I tried a simple, two-line script to see if I could find if there was a ...
3
votes
3answers
3k views

Sending the output from 'dd' to awk/sed/grep

I'm trying to approximate the computer's write speed using dd: dd if=/dev/urandom of=/dev/null bs=1K count=10000 which gives the following output 10000+0 records in 10000+0 records out 10240000 ...
3
votes
1answer
321 views

Null input in a text file

I have a script that creates users in Linux as well as Oracle, when I create multiple users I use the following: cat /path/path/file.txt | while read USER PASS ORAUSER ROLE do However ...
1
vote
1answer
720 views

How should I check to see if the remote smb serv is mounted?

I'm pretty new to mount. Basically, I have a remote SMB serv on the local network that I want copy images from a directory on, then repeat every 5 min. I think what I need to do is make a script that ...
5
votes
2answers
4k views

missing argument to find -exec

I want to remove certain files using find and -exec. But unlikely bash tells me, that I'm "missing" some argument. find . -name *.png -exec rm {} /; what do I miss? same "missing argument" return ...
11
votes
2answers
2k views

Use find command to convert markdown files to html

Lets suppose I have files on my harddisk having extensions as .md. I want to convert all those files to .html through find and the -exec option. The command to convert a markdown file to html is ...
0
votes
1answer
95 views

Why does this compound command report errors when copying directories? [duplicate]

Possible Duplicate: Why does this compound command report errors when copying directories? if one executes the following two commands in one line, as follows, rm -rf dir ; cp -r dir2 ...
0
votes
2answers
204 views

Why does this compound command report errors when copying directories?

if one executes the following two commands in one line, as follows, rm -rf dir ; cp -r dir2 dir it may complain that cp can not create directory dir/subdir: File exists but if these two commands ...
0
votes
2answers
146 views

HDI script fixed (non-interactive) input in a command-line gui program?

I want to create a simple script that initiates a simple gui-based program (think ncurses-style, text-based graphics in a shell) in Debian. I only access the server through SSH, so I can't do ...
1
vote
1answer
4k views

Bash: kill background jobs

Is there a more compact form of killing background jobs than: for i in {1..5}; do kill %$i; done Also, {1..5} obviously has a hard-coded magic number in it, how can I make it "N" with N being the ...
3
votes
6answers
5k views

Difference between “echo $SHELL” and “which bash”

I am trying to determine the location of bash interpreter on my Solaris system and I am a bit confused. When I type: echo $SHELL The resulting path is: /bin/bash And when I type: which bash I ...
3
votes
2answers
3k views

File not found for file which is there [duplicate]

Possible Duplicate: “No such file or directory” lies on Optware installed binaries I am currently trying to get some piece of hardware to work on an embedded device. One part of ...
2
votes
1answer
3k views

How to Install BASH in FreeBSD

I really find that using bash helps a lot, when you need to retrieve strings of text that you used previously. But how can I install it on FreeBSD? I have tried typing bash into the terminal, but ...
2
votes
1answer
692 views

git tab-completion does not work on Debian Wheezy but works on Squeeze

My question is about git command tab-completion, i.e. when I type git stat and hit Tab, it completes the command line to git status. (Where applicable, this also works with remote names and branch ...
5
votes
2answers
939 views

Disable mail check on login?

When I login to console, e.g tty1, I usually see a message No mail, I know there's some program checking email on login, but I don't use that, how can I disable that command ? I tried to grep from ...
2
votes
5answers
3k views

Perl script, do cd on terminal

In Script to change current directory (cd, pwd) it is shown how to run a bash script that changes terminal directory. But how do i run a perl script that runs a bash script that changes terminal ...
23
votes
1answer
2k views

Why can't root execute when executable bits are not set?

root user can write to a file even if its write permissions are not set. root user can read a file even if its read permissions are not set. root user can cd into a directory even if its execute ...
2
votes
3answers
525 views

When the lines of a file or directory get too long, upgrade to ls list format?

Is there a way I can do this? For example if a gets a long name like: i-have-names-that-are-too-long-to-describe/ i-have-names-that-are-too-long-to-describe-2/ ...
2
votes
2answers
408 views

How come lvextend allocates less than the specified amount of space?

I am trying to extend a volume, let's call it /dev/vol1. I see the initial volume size is 500MB when I call: df --block-size=M /dev/vol1 then to extend it 100MB more I call: lvextend -L+100M ...
3
votes
1answer
166 views

On OS X, how do I log in interactively as root starting from my normal user account?

I have been doing this for a while: sudo su - but it uses 'sh' rather than 'bash', which is what I'd like to do. Which command will log me in as root and get me a bash shell even if that's not the ...
2
votes
2answers
348 views

Bash Process Substitution does not work as 'root' on OS X

OS X 10.6.8, if I use Bash Process Substitution as 'root', it just doesn't work. Is it supposed to be so? Why? Note: here's what I mean... "<(list)" mysql -D robottinosino < <(echo ...
5
votes
2answers
5k views

Bash: integer expression expected, using read/test

I'm learning the basics of shell programming, so I wrote something simple like #!/bin/bash read var1 read var2 if [ var1 -lt var2 ]; then echo "var1 is lt var2" else echo "var2 is lt var1" fi ...
10
votes
2answers
784 views

How to exit bash history search mode?

In Ubuntu 12.04 I use CTRL-R to enter a reverse history search. If the command I want is not found (after repeated CTRL-R), how do I immediately exit back to the (empty) command prompt with no ...
27
votes
4answers
5k views

How to do nothing forever in an elegant way?

I have a program which produces useful information on stdout but also reads from stdin. I want to redirect its standard output to a file without providing anything on standard input. So far, so good: ...
13
votes
1answer
5k views

Are there naming conventions for variables in shell scripts?

Most languages have naming conventions for variables, the most common style I see in shell scripts is MY_VARIABLE=foo. Is this the convention or is it only for global variables? What about variables ...
1
vote
1answer
372 views

How to configure ADSL connection using bash?

I know it's possible to configure the modem to automatically connect the internet using a browser, but I want to do it using bash. I would like the network to automatically connect when the system ...
6
votes
2answers
650 views

Run a script automatically as I switch to a directory [duplicate]

Possible Duplicate: Execute bash scripts on entering a directory I am running an environment which requires some very specific tool versions. The commands to set up the environment are in a ...
-1
votes
1answer
2k views

Check if the command exists in bash

I want to check if a given command exists in bash and I care only about the native commands of the bash and not the scripts written by the user. When I refer to native commands I mean all those ...
2
votes
1answer
261 views

How to add variables to script output?

A program to calculate statistics outputs its data in this format Calc_Statistics -input_data ...
5
votes
2answers
644 views

How to parse many variables to bash?

A program outputs its data in this format: n=4607356 null_cells=5668556 cells=10275912 min=0.0433306089835241 max=0.53108499199152 range=0.487754383007996 mean=0.40320252333736 ...
4
votes
3answers
3k views

Bash: How do I move my cursor to the left a word-at-a-time?

In OSX I can just hold down the option key and press the left cursor key until I get to the word I need to edit (or in Vi I can just hit b, but I haven't been able to figure out how to do this in ...
-1
votes
3answers
302 views

Duplicate bash prompts

I'm having an interesting issue with XFCE Terminal/Gnome Terminal (not reproducible in XTerm), where executing bash or logging in using login or su will open a new Bash instance inside a Bash instance ...
3
votes
4answers
552 views

Prevent a command from being executed after another command

I would like the shell to warn me for potential errors I'm about to make. How can I prevent a command cmd2 from being executed after cmd1. For example: $ tar tf file.tar $ rm !$ Here, I just ...
5
votes
3answers
11k views

Automating textual input from a bash script without using EOF

I'm running Ubuntu Linux. Suppose there is a program called myprogram. This program prompts the user for input; specifically, the user must type an integer when prompted and press Enter. I would ...
16
votes
2answers
3k views

Does redirecting output to a file apply a lock on the file?

If I have a command $ ./script >> file.log that gets called twice, with the second call occurring before the first one ends, what happens? Does the first call get an exclusive lock on the ...
0
votes
1answer
408 views

How do I escape a dot character for an rsync command? [closed]

I'm trying to do... ssh -av -e deploy@domain.com:/var/www/domain.com /Users/user/workspace/domain But it's outputting this (I presume because of the period character): OpenSSH_5.6p1, OpenSSL ...
3
votes
2answers
827 views

Search for files with a specific size inside recursive zipped archives

I have a folder with several files. These files are either .xml or .zip files. These .zip files contain .xml and/or .zip files. These .zip contains also .xml or .zip, and so on... until we finally ...
6
votes
1answer
680 views

Peculiar piping grep/head behavior

I'm helping the netadmin here with a perl regex to automate operating on some snapshots from our SAN and our scripts does stuff like this: varinit1=$(iscsiadm -m session | grep rbmsdata1 | head -n1 | ...
3
votes
2answers
2k views

Use `ln` to create a missing directory

So I'm writing a small package manager, and a problem I've run into is making the symbolic links to files. It installs the package to /usr/pkg/name-version, and then reads a file to determine what ...
2
votes
4answers
664 views

Stripping all vowels but the first from a set of strings

I have a string comprised of multiple substrings, separated by underscores. For example: AbcdAEfd_hEgdgE_AbAAAAA. I need to remove all vowels except the first from each substring. So: AbcdAEfd -> ...
11
votes
6answers
10k views

Terminating an infinite loop

I have a command that I want to have run again automatically each time it terminates, so I ran something like this: while [ 1 ]; do COMMAND; done; but if I can't stop the loop with Ctrl-c as that ...
6
votes
1answer
5k views

export HTTP_PROXY and special characters in passwd

Suppose for the sake of argument my password below is abc123@ I need to authenticate my linux machine through a corporate proxy to get patches and updates... normally I'd use this: export ...
6
votes
3answers
513 views

Bash autocomplete gives different file name than ls

An incredibly strange thing just happened. Through a serious typo, I entered cp filename.xsl .^?~ Yeah, that's right, dot-caret-questionmark-tilde! Truth is stranger than fiction. It gets weirder. ...
1
vote
3answers
851 views

Error in Script. Command find is skipping folders with space character

I need a script that counts the files in a directory (and sub). I've taken the followed script, and changed it to my need. It works like it should, except for folders with space characters. I'm ...
3
votes
2answers
5k views

SSH + Sudo + Expect in Bash script: Run command with sudo in remote machine

I am trying to automate the deploy of some .deb packages with an script. I want to execute sudo dpkg -i $myDeb.deb in a list of remote machines I can access with ssh. I've tried to automate the ...
5
votes
2answers
712 views

Wrapping a shell script with tee

There is a bash script which prints some logs and allows some arguments. The script prints the logs to STDOUT. Let's say the script's name is AAA.sh I'd also like to make the script to print the logs ...
4
votes
2answers
282 views

Exiting a pipeline if a former command fails

I'm trying to check the number of running and queued PBS jobs by parsing the output of qstat -tn1 from a bash script. So far, this has worked: count () { qstat -tn1 | awk ' BEGIN { R = 0; ...