Strings are typically delimited by quotes, which raises the problem of dealing with strings that include quotes.

learn more… | top users | synonyms

1
vote
2answers
171 views

Why does “grep '.*[s]' file” work and “grep .*[s] file” doesn't?

Comparing grep '.*[s]' file with grep .*[s] file Why do you need quotation marks to let this work properly? In the second case, grep seems trying to inspect every file with a period.
0
votes
2answers
12 views

tcpdump filter expression breaks via adb

I installed tcpdump on my Android tablet and am running commands from a root adb shell. I'm working from the tcpdump man page examples, specifically this one: To print all IPv4 HTTP packets to and ...
0
votes
1answer
30 views

UnixWare 7 fails to pass variable to Linux

I'm new to Bash and I have a problem that find difficult to solve, may be easy for some. I have a really old SCO UnixWare 7 system with no SSH only RSH available. SCO doesn't exist anymore , I ...
3
votes
4answers
76 views

fgrep beginning of line?

I'd like to use fgrep to handle searching literal words with periods and other meta-characters in grep, but I need to ensure the word is at the beginning of the line. For example, fgrep 'miss.' will ...
0
votes
1answer
57 views

Run a command under sudo over SSH

I am accessing remote machine in Linux using Bash scripting.My code is as follows #!/bin/bash ssh -i manu_bp.pem ubuntu@54.68.67.68 <<EOF sudo -s cat ...
1
vote
2answers
19 views

Quoting / escaping / expansion issue in “command in a variable”

I want to run a command such as this in a bash script: freebcp <authentication and other parameters> -t "," -r "\r\n" When run directly on the command line, the command works as expected. But ...
4
votes
5answers
229 views

How do you interact with a file named “!!”? [duplicate]

Out of rage, I quit vim by using :wq!!!. This created a file named !!. Given that !! references the previous command, attempting to interact with it yields interesting results. I tried rm ./!! and ...
2
votes
2answers
23 views

variable substitution in CLI and for loops

I am pretty sure this has been asked already in some form, I just cannot come up with a good find to search it. I want to have a script that do things N times and to which I can pass as a variable ...
1
vote
3answers
26 views

UNC Argument in bash scipt

I want to create a bash script with a "pure" UNC (i.e. I do not want to escape the backslashes literally) as an argument, i.e. something like: ./foo \\my\share\is\here However, as is natural, the ...
2
votes
1answer
29 views

Export path with space in directory name [duplicate]

I have a path "/third/party/city of las vegas" when cd the path I use "/third/party/city of las vegas". In .profile file I have exported the path to a variable as follows export ...
2
votes
2answers
68 views

How to use variables inside single quotes

I have an application which takes as an input attributes in double quotes embedded in single quotes. Take for example this right command: command -p 'cluster="cl1"' In order to automate it, I ...
2
votes
0answers
55 views

Is there a difference between double quoting a variable or a whole line in echo

When you type, for example, echo Variable "$var" is not initialised. and echo "Variable $var is not initialised." the front end result is the exact same (as far as I know, at least). But I was ...
2
votes
3answers
84 views

Variable expansion in Bash

I tried the following commands variable='one|name' echo $variable The output is one|name whereas echo one|name gives an error No command 'name' found. This is reasonable because bash treats | as ...
0
votes
1answer
28 views

Prepending text read from a file on the top of another file [duplicate]

I want to add "void mainfunction()" on the top of a file. I am reading the actual name of the file from another file and the name of the main function from another file. I was using sed -i '1i void ...
1
vote
1answer
66 views

awk in ssh in su in a command substitution

I am creating a script that will ssh to a host and print all the user accounts and when they will expire. On a host I can run awk -F':' '{ print $1}' /etc/passwd and it will give me a list of all ...
2
votes
1answer
45 views

How to use variables in sed command

I'm trying to run sed -i "/$variable/c \$variable1' file.txt But it's not displaying any change in the file: file.txt. But the same command, with out the variables works fine: sed -i "/variable/c ...
4
votes
3answers
143 views

Using | pipe character from a $variable makes it treat as just another argument in bash; how to escape it?

I have a bash script like this export pipedargument="| sort -n" ls $pipedargument But it gives the error ls: |: No such file or directory ls: sort: No such file or directory It seems to be ...
4
votes
2answers
164 views

Running commands stored in shell variables

The following works in my shell (zsh): > FOO='ls' > $FOO file1 file2 but the following doesn't: > FOO='emacs -nw' > $FOO zsh: command not found: emacs -nw even though invoking emacs ...
0
votes
2answers
55 views

Bash Script Parsing Argument not working correctly

i have the following bash script (taken from FFmpeg) #!/bin/bash ################################################################################ # # Script name: MultiMedia Concat Script (mmcat) # ...
2
votes
2answers
79 views

Is there a reason to quote the exit status $? variable?

I was looking at Google's style guides for their bash scripts, and saw that they quote the exit status variable $? here. if [[ "$?" -ne 0 ]]; then error_message fi I thought return values are ...
1
vote
1answer
55 views

Remote ssh command not sending echo variable from a ksh script on AIX

I'm need to get the value of a variable from a remote host in a script using SSH and have to source an environment file first that does a shift at the end of its run. The command works locally and I ...
2
votes
2answers
60 views

How do I write a command for the Exec key in a .desktop file containing a reserved character correctly?

I'm trying to make a .desktop file for Minecraft. Nothing appears to happen upon executing the file. I've tried assigning the Exec key as follows: Exec= java -jar "~/.minecraft/Minecraft.jar" Exec= ...
1
vote
1answer
34 views

why does grep '\;.' expand to grep '\''\;.'\''' when executed over ssh?

$cat test.sh ssh HOST -l root -o StrictHostKeyChecking=no -q "/bin/bash -l -c /bin/env | grep -w PATH | grep '\;.'" $bash -x test.sh + ssh HOST -l root -o StrictHostKeyChecking=no -q '/bin/bash -l -c ...
1
vote
0answers
18 views

Take the unknown contents of variable as literal in sed [duplicate]

I have two files: a.patterns contains patterns in a one per line way "`" "^" "<" "<(" "<)" "<[" "=" ">" "_;|^+*+?@" and b.data contains comma separated values. 1,1,0,"*",1 ...
8
votes
2answers
160 views

How can I conditionally pass a subshell through 'time'?

I have a setup script for a Vagrant box where I used to measure single steps with time. Now I would like to conditionally enable or disable the time measurements. For example, previously a line would ...
3
votes
1answer
48 views

Problem with passing parameters containing spaces and wild card characters

I have a problem passing parameters if the parameters may contain wildcards and/or spaces, if those parameters are optional. Since this sounds pretty abstract, let's have a small example: The ...
0
votes
1answer
32 views

Remove a folder with the same name as an environment variable

I was messing around with a log4j properties file and accidently made a folder with the following text ${foo} however I also have an environment variable named foo that points to a folder so thus if I ...
3
votes
1answer
67 views

sed repeating the last line in the stream

I have code in a script similar to this... smbconffile="/etc/samba/smb.conf" sed -i 's/.*[\[CMI\]]/\[CMI\$\]/' $smbconffile && echo "Success" || "Failed" sed -i 's/.*[\[LOCAL\]]/\[LOCAL\$\]/' ...
0
votes
2answers
49 views

How do I handle special characters like a bracket in a bash script?

I am trying to get the output of some programs and assign them to variables. I am using backticks to do it, but I can switch to a different method if necessary. What I notice is that often I do not ...
4
votes
2answers
246 views

How to quote arguments with xargs

Suppose that I want to delete all files in a folder that are greater than 1 MB. $ find . -size +1M | xargs -0 rm This will not delete files that have space in their names. So I want it to quote all ...
2
votes
3answers
45 views

SSH command with file redirect not working

I want the following command's result to redirect into a file on the remote server, as I want only unique lines in my authorized_keys file: ssh root@10.100.10.26 awk '!seen[$0]++' ...
42
votes
1answer
963 views

Security implications of forgetting to quote a variable in bash/POSIX shells

If you've been following unix.stackexchange.com for a while, you should hopefully know by now that leaving a variable unquoted in list context (as in echo $var) in Bourne/POSIX shells (zsh being the ...
2
votes
1answer
23 views

rsync exclude-from directory with space

I am trying to exclude "Mendeley Desktop" directory for rsync. The exclude-from= is as: Downloads *.o *.iso Dropbox Documents/Mendeley\ Desktop but rsync is still backing up the Mendeley Desktop. ...
2
votes
2answers
58 views

Event not found in sed call in csh script

I tried the code as given on delete text between curly brackets however I am facing this different error regarding event in sed. file contains: This is { {the multiline text} file } that wants { ...
6
votes
4answers
324 views

what's the difference between using 'single quotes' or not in find command

find ~/ -name *test.txt find ~/ -name '*test.txt' Can anyone help me to construct an example where the first form fails but the second still works. And tell me the difference between them.Thanks!
2
votes
3answers
81 views

How to parse env variable in a quoted string?

I'm having a hard time getting the value of an environment variable ($GHREPO) in a quoted string. Here is the command I'm running. I'm trying to make a directory with the value of ...
3
votes
2answers
155 views

single quote within double quotes and the bash reference manual

In section 3.1.2.3 titled Double Quotes, the bash manual says: Enclosing characters in double quotes (‘"’) preserves the literal value of all characters within the quotes, with the exception ...
13
votes
2answers
856 views

How can variables use “~” for cd'ing?

How can I use a variable - $BASE in my cd. I tried the following but I get an error $ cd ~/z/repo_1_ruby_193/ 23:23:57 durrantm Castle2012 /home/durrantm/z/repo_1_ruby_193 $ BASE="~/z" 23:24:03 ...
2
votes
3answers
336 views

Bash File existence test is always true

I have the following lines of bash script to test whether a file exists: MYAPPPATH=$(find $APPDIR -iname myapp* -print) if [ -e $MYAPPPATH ] then echo "File exists" fi However when file ...
0
votes
2answers
42 views

how to insert backslash at the front of # symbol?

In bash programming, given a variable, say varA, that store a string containing # symbol. Let's assume varA contain this value: ASD# 1, I need to append a backslash \ at the front of #, so the output ...
1
vote
1answer
31 views

Using double or no quotes with wildcards

I came across this article which attempts to explain the find command.It gives an example of find /tmp -iname "data*.txt" now this article here states that Double quotes do not suppress the ...
2
votes
2answers
256 views

Left and right square brackets treated differently by sed/bash

I have a file with the following contents: [root@server list]# cat filenames.txt [AAA','ACMEDEMO2','ACMEDEMO3','ACMEDEMO4','RENTCOGH','TESTENT','DORASINE','LOKAWINK','BBB] [root@qa4app01 list]# I ...
3
votes
3answers
111 views

Why does my grep expression need to use $'string' to match tab characters?

If you take this code: echo -e '\t\t\tString' | grep '^[\t]*String' the result is blank because it doesn't match, yet this: echo -e '\t\t\tString' | grep $'^[\t]*String' works. I swear that I ...
2
votes
1answer
49 views

Help with using quotes in grep searches

I have a file with variables in it of the form a(i)%b(j)%c where the a, b, and c are always the same, but the indices i and j may be different (including multiple characters). So I've played around ...
0
votes
2answers
58 views

Can't use argument in bash date calculation script

The following bash script won't work. I need to calculate the date depending on the number of days since 14th Oct 1582, where the argument will be the number of days. d="$1" date -d '14 Oct 1582 + ...
0
votes
1answer
17 views

Loop across url with static tokens with Oauth

I need to write a loop where I need to pass a "token" (which is fixed) and a variable (i) in the url. Is there any way I can achieve that? I wrote the following code but it is not working. If I put ...
0
votes
1answer
33 views

Trying to make aliases that open the last modified file

One thing that I frequently do is edit the most recently modified files, so instead of typing "ls -lr" and then "vim lastfile", I thought I would make some shortcuts in my ~/.bash_profile file: alias ...
0
votes
1answer
75 views

How to escape unbalanced brackets or slash in sed?

I'm trying to use sed, but my pattern contains [] brackets and slashes (/). I've tried quotes, but it doesn't help. How do I escape it? Examples: $ sed -i'.bak' "s/^includes[] =/;includes[] ...
3
votes
2answers
47 views

echoing basename under xargs?

I have the following command : ls /some/path/*dat | xargs -n 1 -I @ sh -c "echo `basename @`" with the directory /some/path/ containing : /some/path/a /some/path/b /some/path/c /some/path/d I ...
2
votes
1answer
279 views

Shell script, find -name, and wildcard expansion

I'm trying to use find -name in a sh script with a previously computed complex argument for the condition. Simplified, it goes like cond="-name '*.txt*" find . $cond -ls But now I have the problem ...