All Questions
12
questions
73
votes
1
answer
13k
views
What is the difference between the "...", '...', $'...', and $"..." quotes in the shell?
Sometimes I see shell scripts use all of these different ways of quoting some text: "...", '...', $'...', and $"...". Why are there so many different kinds of quote being used?
Do ...
- 77.2k
6
votes
3
answers
7k
views
shell: Quote string with single quotes rather than backslashes
How can I quote a string with single quotes?
Eg, I can do:
$ printf "%q\n" 'two words'
two\ words
$
Is there a way to get a single- (or double-) quoted string as output, ie:
$ MAGIC 'two words'
'...
- 31.3k
1
vote
1
answer
1k
views
Invoking zmv from bash
I have recently discovered this technique for renaming files using zsh:
autoload zmv
zmv '(*).JPG' '$1.jpg'
which I can also write as:
autoload zmv; zmv '(*).JPG' '$1.jpg'
This works as advertised ...
- 233
7
votes
1
answer
3k
views
Why does `zip` in a for loop work when the file exists, but not when it doesn't?
I have a directory that contains several sub-directories. There is a question about zipping the files that contains an answer that I ever-so-slightly modified for my needs.
for i in */; do zip "zips/...
- 11.9k
3
votes
1
answer
115
views
zsh fail to keep unquoted `$*` and `$@` equal
All shells tested do the same for the (quoted) pair "$*" and "$@" with this code:
c='set a b @ c; IFS=:,@ ; a=$(printf "<%s> " "$*"); b=$(printf "<%s> " "$@"); printf "%-20s and %-20s\n" "...
user79743
8
votes
2
answers
3k
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 -...
- 41.6k
13
votes
3
answers
30k
views
Treatment of backslashes across shells
How do echo and printf treat backslashes in zsh, bash and other shells?
Under zsh I get the following behavior:
$ echo "foo\bar\baz"
foaaz
$ echo "foo\\bar\\baz"
foaaz
$ echo 'foo\...
- 41.6k
181
votes
1
answer
78k
views
When is double-quoting necessary?
The old advice used to be to double-quote any expression involving a $VARIABLE, at least if one wanted it to be interpreted by the shell as one single item, otherwise, any spaces in the content of $...
- 15.7k
3
votes
4
answers
2k
views
Piping paths with different types of quotes for slash substitution
I would like to use sed to convert a path with backslashes to the same path with forward slashes:
E.g.
I would like to pipe \\path\to\file\ and obtain /path/to/file
None of the following commands ...
- 41.6k
1
vote
2
answers
3k
views
Weird zsh grep -P behaviour
I connect to server with PuTTY from Windows.
I have a long yet not touched (I suppose) by hands of local admin config:
$ cat /opt/jira/.subversion/config
...
### must be enabled, which is ...
- 144
17
votes
1
answer
22k
views
Wrapping a command that includes single and double quotes for another command
I recently learned about watch, but am having trouble making it work with relatively sophisticated commands.
For example, I would like to ask watch to run the following command on zsh every three ...
- 41.6k
29
votes
3
answers
30k
views
Escaping quotes in zsh alias
Following on from this question about stripping newlines out of text, I want to turn this into a zsh alias as follows:
alias striplines=' awk " /^$/ {print \"\n\"; } /./ {printf( \" %s \",$0);}"'
I'...
- 3,713