Trying to write a simple script to copy some files in OS X 10.9.
Here's the content..
SRC_DIR="~/Library/Preferences-Old"
DST_DIR="~/Library/Preferences"
FILEN="test.txt"
cp $SRC_DIR/$FILEN $DST_DIR
Gives me the output:
cp: ~/Library/Preferences-Old/test.txt: No such file or directory
Of course, the above is wrong. The exact same cp command in terminal directly does the trick. What am I doing wrong here?
~ is one of the few exceptions to the rule "When in doubt, quote". As others have pointed out, a quoted ~ is not subject to expansion. However, you can still quote the rest of the string:
SRC_DIR=~"/Library/Preferences-Old"
DST_DIR=~"/Library/Preferences"
Note that depending on the values assigned to the two *_DIR variables, it's not enough to quote the values being assigned; you still need to quote their expansions.
FILEN="test.txt"
cp "$SRC_DIR/$FILEN" "$DST_DIR"
Your double-quotes are preventing the shell from converting your ~ into an actual path. Observe:
$ echo ~
/home/politank_z
$ echo "~"
~
~ isn't an actual location, it is shorthand for the path of your home directory.
As already mentioned double-quotes disabled ~ expansion.
Better approach is to use HOME variable:
SRC_DIR="$HOME/Library/Preferences-Old"
DST_DIR="$HOME/Library/Preferences"
Related
I have environment variable export MY_WORK_DIR="~/project".
While I'm using below command, it give me an error:
realpath $MY_WORK_DIR
realpath: '~/project': No such file or directory
In my guess, the ~ is not processed while using this env variable.
BTW, export MY_WORK_DIR=~/project is not an option for me. ~ should be in the string.
Could you please guide me how to get real path from envrionment variable ~/project ?
EDIT
Sorry. The variable is from other app so I cannot modify the environment variable which contains tilde. (Storing variable with tilde expanded form is not an option).
EDIT2
Is it safe to use eval command like this? eval "echo ${MY_WORK_DIR}". It works for my use.
I wouldn't use eval if I can avoid it. Especially in the way you are doing it, this is an invitation to do havoc by embedding dangerous code into MY_WORK_DIR.
A cheap solution for your concrete example would be to do a
if [[ ${MY_WORK_DIR:0:1} == '~' ]]
then
MY_WORK_DIR="$HOME/${MY_WORK_DIR:1}"
fi
which chops off the annoying ~ and prepends your home directory. But this would fail if MY_WORK_DIR is set to, say, ~einstein/project.
In this case, you would have to extract the user name (einstein) and search the home directory for this user.
Following steps can provide a resolution:
You need to replace "~" with the full path of the project directory.
Use pwd command to identify the full path of the project directory; e.g. /root/Documents/project is the full path you get.
Execute this command export MY_WORK_PROJECT=/root/Documents/project
Execute this command echo $MY_WORK_PROJECT so you should get this result
/root/Documents/project
my script is very simple, i try to store a path in a variable then use it to copy files, the script is longer, a lot of copys, but using the same variable:
mainserverapp="${HOME}/Dropbox/servers/app-env-files"
cp -av "${mainserverapp}/.env*" ./
but i get this error:
cp: cannot stat '/home/.../Dropbox/servers/app-env-files/.env*': No such file or directory
but the folder exist if i do a 'ls '
something is happening with the variable... where is my error?
UPDATE:
i think i find it !!! the problem is the asterisk , any solution to don't copy file by file?
The asterisk (*) is expanded only when it is not inside quotes and not escaped.
On "${mainserverapp}/.env*" only $mainserverapp is replaced with its value, the * is used as it is.
Move the asterisk outside the quotes:
cp -av "${mainserverapp}"/.env* ./
You can write it "${mainserverapp}/.env"* as well but it makes more sense to put inside quotes only the dynamic part, that get replaced with a value you cannot know. .env does not cause issues, it doesn't need to be quoted. And .env* represents a logical part of the expression, the files whose names start with .env.
Read about "Filename Expansion" in the Bash documentation.
I want to put my ~/Library/Application Support/ directory to a variable in my ~/.bash_profile` to make it easier to reference from within Terminal. I first attempted to define it as follows:
export L=~/Library/Application\ Support
However, when I tried to source ~/.bash_profile and then called ls $L, I got an error: /Users/username/Library/Application: Not a directory.
However, no matter how I define it I cannot define it properly, as far as I came up with the way to define it. Here's the list that I tried, but none of them worked properly.
~/Library/Application Support
"~/Library/Application Support"
"~/Library/Application\ Support"
So is it feasible to store a string which includes a whitespace to a variable in bash to begin with?
Your export statement is fine; the space is properly escaped. You just need to quote the expansion of the parameter, so that bash gives a single argument to the ls command:
ls "$L"
Autoconf scripts have trouble with a filename or pathname with spaces. For example,
./configure CPPFLAGS="-I\"/path with space\""
results in (config.log):
configure:3012: gcc -I"/path with space" conftest.c >&5
gcc: with: No such file or directory
gcc: space": No such file or directory
The compile command from ./configure is ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5' and I am not able to modify this (I could perhaps, but working around autoconf in this way is not a general solution).
I think it comes down to getting a shell variable that contains spaces to be parsed as a single command line variable rather than split at spaces. The simplest shell example I can come up with is to create a file with spaces and attempt to list is with ls with a shell variable as the argument to ls:
$ touch "a b"
$ file="a b"
$ ls $file
ls: a: No such file or directory
ls: b: No such file or directory
This works, but is illegal since in autoconf I can't modify the shell code:
$ ls "$file"
a b
None of the following attempts at quoting things work:
$ file="\"a \"b"; ls $file
ls: "a: No such file or directory
ls: b": No such file or directory
$ file="a\ b"
$ file="a\\ b"
$ file="`echo \\"a b\\"`"
and so on.
Is this impossible to accomplish in shell scripts? Is there a magical quoting that will expand a shell variable with spaces into a single command line argument?
You should try to set the $IFS environment variable.
from man bash(1):
IFS - The Internal Field Separator that is used for word splitting
after expansion and to split lines into words with the read builtin
command. The default value is ''space tab newline''.
For example
IFS=<C-v C-m> # newline
file="a b"
touch $file
ls $file
Don't forget to set $IFS back or strange things will happen.
if you give command
gcc -I"x y z"
in a shell then certainly the single command line parameter "-Ix y z" will be passed to gcc. There is no question to that. That's the whole meaning of double quotes: things inside double quotes are NOT subject to field splitting, and so not subject to $IFS either, for instance.
But you need to be careful about the number of quotes you need. For instance, if you say
file="a b" # 1
and then you say
ls $file # 2
what happens is that the file variable's contents are 'a b', not '"a b"', because the double quotes were "eaten" when line 1 was parsed. The replaced value is then field-separated and you get ls on two files 'a' and 'b'. The correct way to get what you want is
file="a b"; ls "$file"
Now the problem in your original case is that when you set a variable to a string that CONTAINS double quotes, the double quotes are later not interpreted as shell quote symbols but just as normal letters. Which is why when you do something like
file="\"a b\""; ls $file
actually the shell tokenizes the contents of the file variable into '"a' and 'b"' when the ls command is analyzed; the double quote is no longer a shell quote character but just part of the variable's contents. It's analogous to that if you set
file="\$HOME"; ls $file
you get an error that '$HOME' directory does not exist---no environment variable lookup takes place.
So your best options are
Hack autoconf
Do not use path names with spaces (best solution)
Using space in directory names in the Unix world is simply asking for trouble. It's not just the problem of quoting in shell scripts (which needs to be done right anyway): some tools simply cannot cope with spaces in filenames. For instance, you can't (portably) write a Makefile rule that says build baz.o from foo bar/baz.c.
In the case of CPPFLAGS above, I would try one of the following (in order of preference):
Fix the system not use use any space in directory names.
Write a small wrapper around the compiler and call ./configure CC=mygcc. In that case mygcc might be:
#!/bin/sh
gcc "-I/foo bar/include" "$#"
Create a symbolic link (e.g., /tmp/mypath) to the dreaded path and use CPPFLAGS=-I/tmp/mypath.
You want to quote the entire argument, in either of these ways:
./configure "CPPFLAGS=-I/path with space"
./configure CPPFLAGS="-I/path with space"
The ./configure command then sees a single argument
"CPPFLAGS=-I/path with space"
which is parsed as a parameter named«CPPFLAGS» having the value«-I/path with space» (brackets added for clarity).
Using quotes is interesting. From (lightly) reading the bash man page I thought you had to escape the space with \, thus "/path with space" becomes /path\ with\ space I've never tried the quotes, but it seems that it doesn't work generally (your ls example). Escaping works with ls without quoting and without changing IFS.
What happens if you use the "escaping spaces" format of the command?
$ file="\"a b\""
$ eval ls $file
Everything depends on how the variable is used. First, note that if you are using Autoconf, this probably means that make will be used eventually, so that the rules are dictated by make, and in particular, the default make rules. Even though you may want to use your own rules exclusively, things must remain consistent between tools, and some variables have standard meanings, so that you do not want to deviate from them. This is not the case of CPPFLAGS, but this should remain similar to CFLAGS, which is standard. See the POSIX make utility, where variables are simply expanded with standard sh word splitting, which does not provide any quoting mechanism (the field separator is controlled by $IFS, but do not change the IFS variable to accept spaces as normal characters since this will break other things, like being able to provide several -I and/or -L options in such variables with the standard way).
Since there is such a limitation with make, I suppose that it would be useless to try to avoid this limitation in Autoconf.
Now, since a space is necessarily a field separator, the only possibility is to provide pathnames without space characters. If spaces in pathnames were to be supported in the future, this would probably be done via pathname encoding, with decoding at the high-level UI (a bit like with URL's). Alternatively, if you have the choice and really want to use spaces in pathnames, you may use some non-ASCII space (BTW, this is how RISC OS supports space in pathnames, by forcing it to be the no-break space).
I'm using Bash on macOS X and I'd like to create a simple executable script file that would change to another directory when it's run. However, the path to that directory has spaces in it. How the heck do you do this? This is what I have...
Name of file: cdcode
File contents:
cd ~/My Code
Now granted, this isn't a long pathname, but my actual pathname is five directories deep and four of those directories have spaces in the path.
BTW, I've tried cd "~/My Code" and cd "~/My\ Code" and neither of these worked.
When you double-quote a path, you're stopping the tilde expansion. So there are a few ways to do this:
cd ~/"My Code"
cd ~/'My Code'
The tilde is not quoted here, so tilde expansion will still be run.
cd "$HOME/My Code"
You can expand environment variables inside double-quoted strings; this is basically what the tilde expansion is doing
cd ~/My\ Code
You can also escape special characters (such as space) with a backslash.
I found the solution below on this page:
x="test\ me"
eval cd $x
A combination of \ in a double-quoted text constant and an eval before cd makes it work like a charm!
After struggling with the same problem, I tried two different solutions that works:
1. Use double quotes ("") with your variables.
Easiest way just double quotes your variables as pointed in previous answer:
cd "$yourPathWithBlankSpace"
2. Make use of eval.
According to this answer Unix command to escape spaces you can strip blank space then make use of eval, like this:
yourPathEscaped=$(printf %q "$yourPathWithBlankSpace")
eval cd $yourPathEscaped
You can use any of:
cd ~/"My Code"
cd ~/M"y Code"
cd ~/My" Code"
You cannot use:
cd ~"/My Code"
The first works because the shell expands ~/ into $HOME/, and then tacks on My Code without the double quotes. The second fails because there isn't a user called '"' (double quote) for ~" to map to.
cd ~/My\ Code
seems to work for me... If dropping the quotes but keeping the slash doesn't work, can you post some sample code?
This will do it:
cd ~/My\ Code
I've had to use that to work with files stored in the iCloud Drive. You won't want to use double quotes (") as then it must be an absolute path. In other words, you can't combine double quotes with tilde (~).
By way of example I had to use this for a recent project:
cd ~/Library/Mobile\ Documents/com~apple~CloudDocs/Documents/Documents\ -\ My\ iMac/Project
I hope that helps.
A single backslash works for me:
ry4an#ry4an-mini:~$ mkdir "My Code"
ry4an#ry4an-mini:~$ vi todir.sh
ry4an#ry4an-mini:~$ . todir.sh
ry4an#ry4an-mini:My Code$ cat ../todir.sh
#!/bin/sh
cd ~/My\ Code
Are you sure the problem isn't that your shell script is changing directory in its subshell, but then you're back in the main shell (and original dir) when done? I avoided that by using . to run the script in the current shell, though most folks would just use an alias for this. The spaces could be a red herring.
When working under Linux the syntax below is right:
cd ~/My\ Code
However when you're executing your file, use the syntax below:
$ . cdcode
(just '.' and not './')
use double quotes
go ()
{
cd "$*"
}
The very simple way of doing this is-
$ cd My\ Folder
In bash, run DIR command and in the results you would see that the folder or path names having space between them has been written in the results like this -
$dir
My\ Folder
New\ Folder
Use single quotes, like:
myPath=~/'my dir'
cd $myPath
Avoid ~ in scripts; use $HOME instead.
I had a similar problem now were I was using a bash script to dump some data. I ended up creating a symbolic link in the script folder with out any spaces in it. I then pointed my script to the symbolic link and that works fine.
To create your link.
ln -s [TARGET DIRECTORY OR FILE] ./[SHORTCUT]
Mau or may not be of use.
I read all these, and they didn't seem to work on macOS Monterey. I then changed the header from #!/bin/sh to #!/bin/zshand that seemed to do the trick.