The shell is unix's command-line interface. You can type commands in a shell interactively, or write scripts to automate tasks. Use this tag for questions applying to /bin/sh and most compatible shells (ash, bash, ksh, zsh, …).

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224 views

Complicated variable content failed to get into sed

The first line is variable ann hold quite complicated value. The reason I use the second line is because I don't want to change anything in the third line col1content. To change replacement, I just ...
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3answers
162 views

Restructuring directories into a hierarchy

I have the following type of folder structure containing thousands of folders. The folder names are as such with different names etc .test .test.subfolder .test.subfolder.subsubfolder .folder ...
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5answers
8k views

How do I perform an action on all files with a specific extension in subfolders in an elegant way?

My current best bet is: for i in $(find . -name *.jpg); do echo $i; done Problem: does not handle spaces in filenames. Note: I would also love a graphical way of doing this, such as the "tree" ...
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2answers
4k views

print command not found

From the korn shell, I keep getting print command not found. When I run print from the shell, it says the same thing. How would I go about fixing this? printf works fine, but for some reason print is ...
9
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3answers
8k views

Using OR patterns in shell wildcards

Contents of my dir are $ ls -lrt total 0 -rw-r--r-- 1 user1 admin 19 Oct 8 12:31 night.txt -rw-r--r-- 1 user1 admin 19 Oct 8 12:31 noon.txt -rw-r--r-- 1 user1 admin 38 Oct 8 12:31 day.txt I ...
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2answers
1k views

List files created on Sundays

How do I list/find all the files created on Sundays or Mondays? How do I use the date parameter to display them? Something like : ls -f date + %a or find -type f | date +%A or find -type f ...
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4answers
16k views

Calculate variable, and output it to another variable

The only calculator I know is bc. I want to add 1 to a variable, and output to another variable. I got the nextnum variable from counting string in a file: nextnum=`grep -o stringtocount ...
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2answers
18k views

How to change the working directory of invoking shell using a script? [duplicate]

Possible Duplicate: changing current working dir with a script I am trying to create few scripts that would change the working directory of the main shell/terminal. Not able to do so. I ...
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3answers
14k views

Find files which are created a certain time after or before a particular file was created

I need a shell script which finds files which are created 1 hour before or 1 hour after a particular file (test.txt) was created. If I go with find -newer, that means I'd have to create a temporary ...
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6answers
3k views

Why can't I redirect a path name output from one command to “cd”?

I am trying to get cd to accept a directory name redirected to it from another command. Neither of these methods work: $ echo $HOME | cd $ echo $HOME | xargs cd This does work: $ cd $(echo $HOME) ...
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6answers
8k views

ls: Do not show directories that match same pattern in wildcard searches, only files

Supposing I have something like the following, a typical business PC situation: drwxr-xr-x 1 whatever whoever 3 Oct 3 16:40 invoices2009 drwxr-xr-x 1 whatever whoever 4 Oct 3 16:40 ...
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2answers
16k views

/dev/tcp listen instead of nc listen

With a netcat listener like: nc -l <port> < ~/.bashrc I can grab my .bashrc on a new machine (doesn't have nc or LDAP) with: cat < /dev/tcp/<ip>/<port> > ~/.bashrc My ...
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3answers
325 views

When was process substitution first introduced?

I'm curios to know how long process substitution has been around. What shell first had it? When did it get added to other shells?
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3answers
10k views

Recursive glob?

I'd like to write something like this: $ ls **.py in order to get all .py filenames, recursively walking a directory hierarchy. Even if there are .py files to find, the shell (bash) gives this ...
2
votes
1answer
369 views

Why does newgrp change my PS1 and how to prevent it?

I have a customized PS1 to show several parameters. When I switch to a different group using newgrp, it switched my PS1 to default ($) and that is annoying. The default remains even when I switch ...
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1answer
1k views

Bash overwrites the first line, PS1 bash prompt

I have played around with PS1 and PROMPT_COMMAND in bash to create a zsh-style right side prompt. I have a solution who almost works. The problem is that if I write a long line of input, the second ...
5
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1answer
871 views

How does sh -e interact with &?

I'm using sh (dash) on Ubuntu (lucid) and the manpage has this to say about -e: -e errexit If not interactive, exit immediately if any untested command fails. ...
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1answer
201 views

Can we use history file for auditing purpose

We have a common testing environment on AIX for all 15-20 persons. There might be chances that somebody deleted the files mistakenly. In such scenarios, it is very difficult to know who deleted files ...
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4answers
370 views

Follow a moved file to its destination directory

Is there a way to move a file from a directory to another and then cd into the latter in one command? Something like mv /a/file /another/dir && cd _ but without typing second time the ...
3
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3answers
187 views

How can I identify the variant of Unix/Linux from a shell? [duplicate]

Possible Duplicate: How can I get distribution name and version number in a simple shell script? Given a shell, how can I identify the variant of Unix/Linux that is running on a remote ...
3
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2answers
682 views

how to grep for c:\

I'm using cygwin's grep to find all instances of hardcoded paths on c drive. doing: grep -r "c:\\" . gives grep: trailing backslash Does anybody know how I can do this?
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2answers
3k views

Interactively deleting files from a list

I'd like to remove a list of files and be asked for confirmation. The list is in the list.txt file. Why the following command doesn't work properly? while read i; do rm -i $i; done < list.txt ...
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1answer
244 views

Change Directory and List Files [duplicate]

Possible Duplicate: Make cd automatically ls I think that it would be very useful to have a unix utility that combines 'cd' and 'ls' so that when you change your directory, it automatically ...
3
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1answer
11k views

What killed tty main process suddenly?

I'm doing some stress testing of a piece of software that can run shell commands. Periodically, the system logs me out during stress testing. My record of the commands that triggered this always ...
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1answer
4k views

Unique lines based on the first field

How can you find unique lines or duplicate lines in a file based on the content of the first field, or the first n characters ? The uniq command on OS X lacks the -w switch that is available under ...
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2answers
3k views

Reserved characters in file names

I was under the impression that the only character not allowed in file names was /, but I don't seem to be able to create a file whose name contains characters such as *, \, ", :, |, < or > ...
3
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1answer
142 views

the return built-in

According to the Open Group, [t]he return utility shall cause the shell to stop executing the current function or dot script. If the shell is not currently executing a function or dot script, ...
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2answers
391 views

Unzip to location

I am using unzip through putty and it works ok. However, using the same command through a .NET C# SSH library (Renci.SshNet) gives different results. SshClient s = new SshClient("ssh_host", ...
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3answers
4k views

How to know if a file has been written completely?

I have shell script which waits for some files to arrive from remote machine, when it arrives, it cats them to a new file. For that I am using a while loop,like following: while true do if [ ...
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2answers
860 views

Auto-expansion problem with array elements containing an '*' (asterisk)

I'm trying to write me a find script that should later be able to read a list of directories to be excluded from an external file. Whilst I can accomplish that part myself, it's the annoying array ...
3
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3answers
1k views

Is there a way to get *actual* (uninterpreted) shell arguments in a function or script?

I have a function posix that I use in the Git bash shell on Windows to transform DOS-style paths to normal Unix-style paths. Since DOS-style paths use a backslash as separator, I have to quote the ...
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2answers
1k views

Get line number in a Bourne shell script

I'd like to be able to print the current line number in a shell script. I know about the $LINENO variable in Bash shells, but it doesn't seem to exist in Bourne shells. Is there any other variable ...
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1answer
4k views

Substitute pattern within a file with the content of other file

I have a text file (devel.xml). I added the word REPLACETHIS to it in order to replace this string with the content within a different file (temp.txt). The closest thing I have is this: sed -i -e ...
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2answers
148 views

Advanced file filtering

I have 3 distinct folders: history, inbox, backup. I need to copy all the files from 'history' to 'inbox', only if they are not present in 'backup'. How to do this?
0
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1answer
900 views

Shell script to recursively grep data from certain files in the directory and return values to file [closed]

I am making a simple shell script which will minimize the time I spend in searching all directories under a parent directory and grep some things inside some files. Here's my script. #!/bin/sh ...
9
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4answers
22k views

How do I tell if a folder is actually a symlink and how do I fix it if it's broken?

How do I tell if I have a symlink, a shortcut of some sort, or a folder in Linux? Please see following screenshot. As you can see, the ls command lists objects where some are colored in dark blue ...
0
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1answer
287 views

How to run svn when ssh over ssh?

I need to run sudo -u wwwrun sh -c 'svn status -uq /srv/www/htdocs/loquat' over ssh. When using one ssh it works smoothly. Now there is one server that needs to be connected through another server via ...
44
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3answers
39k views

How to remove a single line from history?

I'm working in Mac OSX, so I guess I'm using bash...? Sometimes I enter something that I don't want to be remembered in the history. How do I remove it?
1
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1answer
2k views

How do I safely unmount a network share on Linux STB without crashing (I get GSOD)?

I have a network share named dreambox on C:\dreambox that is shared with the group Everyone in Windows. I have mounted it to /hdd on a Linux-based STB with OpenDreambox (OpenEmbedded) using Telnet ...
2
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1answer
148 views

Extracting some files from a folder and creating a list of these files

I am just a beginner with Unix and so my skills in Unix commands is limited. I am currently dealing with a folder containing about 1000 files and I have to extract some filenames from this folder and ...
21
votes
8answers
5k views

The most universal scripting language for Linux is?

We are writing scripts for Linux systems, there has been some debate over what would be the most universally Linux present scripting language to use. Bash, SH, Posix? What?
8
votes
2answers
12k views

Is it possible for nohup to write the output both to the file nohup.out AND to the screen/terminal?

I am using the bash shell. I frequently use nohup to ensure that my processes are not stopped when I close the shell/terminal that started them. I use a syntax like: nohup myprocess When ...
11
votes
4answers
8k views

Copying a single file to multiple directories using cp

This question is a sequel of sorts to my earlier question, Creating numerous directories using mkdir. I am using the bash shell. I have created fifty directories, each starting with the prefix "s", ...
3
votes
1answer
379 views

Bash script with quotes and spaces

I'm trying to get some nice output out of git: FORMAT='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' LOG_PARAMS="--color --pretty=format:$FORMAT --abbrev-commit ...
4
votes
2answers
4k views

Create and move to a directory in one command - unix [duplicate]

Possible Duplicate: Is there a one-liner that allows me to create a directory and move into it at the same time? I know this is a very basic question but I can't seem to figure out what to ...
21
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5answers
7k views

How can I create an alias for a git [action] command (which includes spaces)?

Most of my my aliases are of this form: alias p='pwd' I want to alias git commit so that it does git commit -v But trying to create an alias with a space gives an error: $ alias 'git commit'='git ...
28
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2answers
8k views

How can I test for POSIX compliance for shell scripts?

Probably the main thing that this website has taught me so far is the importance of writing portable shell scripts. Considering that POSIX is the closest thing to a common standard between all ...
23
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5answers
31k views

How to match case insensitive patterns with ls?

I would like to list all files matching a certain pattern while ignoring the case. For example, I run the following commands: ls *abc* I need to see all the file that have "abc" as a part of the ...
9
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5answers
16k views

Creating numerous directories using mkdir

I would like to create many directories using mkdir. Each directory name will consist of a prefix (a string) and an index (an integer). Suppose that I would like the prefix to be "s" and the indices ...
0
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0answers
68 views

/long/path/to/{multiple, files} syntax? [duplicate]

Possible Duplicate: Quick way to include a directory path when calling mv? Is there any way in bash to type a path once, and then reference several files at once? Here's what I do now: ...