I am making an NW.js app on macOS, and want to run the app in dev mode
by double-clicking on an icon.
In the first step, I'm trying to make my shell script work.
Using VS Code on Windows (I wanted to gain time), I have created a run-nw file at the root of my project, containing this:
#!/bin/bash
cd "src"
npm install
cd ..
./tools/nwjs-sdk-v0.17.3-osx-x64/nwjs.app/Contents/MacOS/nwjs "src" &
but I get this output:
$ sh ./run-nw
: command not found
: No such file or directory
: command not found
: No such file or directory
Usage: npm <command>
where <command> is one of: (snip commands list)
(snip npm help)
npm#3.10.3 /usr/local/lib/node_modules/npm
: command not found
: No such file or directory
: command not found
Some things I don't understand.
It seems that it takes empty lines as commands.
In my editor (VS Code) I have tried to replace \r\n with \n
(in case the \r creates problems) but it changes nothing.
It seems that it doesn't find the folders
(with or without the dirname instruction),
or maybe it doesn't know about the cd command ?
It seems that it doesn't understand the install argument to npm.
The part that really weirds me out, is that it still runs the app
(if I did an npm install manually)...
Not able to make it work properly, and suspecting something weird with
the file itself, I created a new one directly on the Mac, using vim this time.
I entered the exact same instructions, and... now it works without any
issues.
A diff on the two files reveals exactly zero difference.
What can be the difference? What can make the first script not work? How can I find out?
Update
Following the accepted answer's recommendations, after the wrong line
endings came back, I checked multiple things.
It turns out that since I copied my ~/.gitconfig from my Windows
machine, I had autocrlf=true, so every time I modified the bash
file under Windows, it re-set the line endings to \r\n.
So, in addition to running dos2unix (which you will have to
install using Homebrew on a Mac), if you're using Git, check your
.gitconfig file.
Yes. Bash scripts are sensitive to line-endings, both in the script itself and in data it processes. They should have Unix-style line-endings, i.e., each line is terminated with a Line Feed character (decimal 10, hex 0A in ASCII).
DOS/Windows line endings in the script
With Windows or DOS-style line endings , each line is terminated with a Carriage Return followed by a Line Feed character. You can see this otherwise invisible character in the output of cat -v yourfile:
$ cat -v yourfile
#!/bin/bash^M
^M
cd "src"^M
npm install^M
^M
cd ..^M
./tools/nwjs-sdk-v0.17.3-osx-x64/nwjs.app/Contents/MacOS/nwjs "src" &^M
In this case, the carriage return (^M in caret notation or \r in C escape notation) is not treated as whitespace. Bash interprets the first line after the shebang (consisting of a single carriage return character) as the name of a command/program to run.
Since there is no command named ^M, it prints : command not found
Since there is no directory named "src"^M (or src^M), it prints : No such file or directory
It passes install^M instead of install as an argument to npm which causes npm to complain.
DOS/Windows line endings in input data
Like above, if you have an input file with carriage returns:
hello^M
world^M
then it will look completely normal in editors and when writing it to screen, but tools may produce strange results. For example, grep will fail to find lines that are obviously there:
$ grep 'hello$' file.txt || grep -x "hello" file.txt
(no match because the line actually ends in ^M)
Appended text will instead overwrite the line because the carriage returns moves the cursor to the start of the line:
$ sed -e 's/$/!/' file.txt
!ello
!orld
String comparison will seem to fail, even though strings appear to be the same when writing to screen:
$ a="hello"; read b < file.txt
$ if [[ "$a" = "$b" ]]
then echo "Variables are equal."
else echo "Sorry, $a is not equal to $b"
fi
Sorry, hello is not equal to hello
Solutions
The solution is to convert the file to use Unix-style line endings. There are a number of ways this can be accomplished:
This can be done using the dos2unix program:
dos2unix filename
Open the file in a capable text editor (Sublime, Notepad++, not Notepad) and configure it to save files with Unix line endings, e.g., with Vim, run the following command before (re)saving:
:set fileformat=unix
If you have a version of the sed utility that supports the -i or --in-place option, e.g., GNU sed, you could run the following command to strip trailing carriage returns:
sed -i 's/\r$//' filename
With other versions of sed, you could use output redirection to write to a new file. Be sure to use a different filename for the redirection target (it can be renamed later).
sed 's/\r$//' filename > filename.unix
Similarly, the tr translation filter can be used to delete unwanted characters from its input:
tr -d '\r' <filename >filename.unix
Cygwin Bash
With the Bash port for Cygwin, there’s a custom igncr option that can be set to ignore the Carriage Return in line endings (presumably because many of its users use native Windows programs to edit their text files).
This can be enabled for the current shell by running set -o igncr.
Setting this option applies only to the current shell process so it can be useful when sourcing files with extraneous carriage returns. If you regularly encounter shell scripts with DOS line endings and want this option to be set permanently, you could set an environment variable called SHELLOPTS (all capital letters) to include igncr. This environment variable is used by Bash to set shell options when it starts (before reading any startup files).
Useful utilities
The file utility is useful for quickly seeing which line endings are used in a text file. Here’s what it prints for for each file type:
Unix line endings: Bourne-Again shell script, ASCII text executable
Mac line endings: Bourne-Again shell script, ASCII text executable, with CR line terminators
DOS line endings: Bourne-Again shell script, ASCII text executable, with CRLF line terminators
The GNU version of the cat utility has a -v, --show-nonprinting option that displays non-printing characters.
The dos2unix utility is specifically written for converting text files between Unix, Mac and DOS line endings.
Useful links
Wikipedia has an excellent article covering the many different ways of marking the end of a line of text, the history of such encodings and how newlines are treated in different operating systems, programming languages and Internet protocols (e.g., FTP).
Files with classic Mac OS line endings
With Classic Mac OS (pre-OS X), each line was terminated with a Carriage Return (decimal 13, hex 0D in ASCII). If a script file was saved with such line endings, Bash would only see one long line like so:
#!/bin/bash^M^Mcd "src"^Mnpm install^M^Mcd ..^M./tools/nwjs-sdk-v0.17.3-osx-x64/nwjs.app/Contents/MacOS/nwjs "src" &^M
Since this single long line begins with an octothorpe (#), Bash treats the line (and the whole file) as a single comment.
Note: In 2001, Apple launched Mac OS X which was based on the BSD-derived NeXTSTEP operating system. As a result, OS X also uses Unix-style LF-only line endings and since then, text files terminated with a CR have become extremely rare. Nevertheless, I think it’s worthwhile to show how Bash would attempt to interpret such files.
On JetBrains products (PyCharm, PHPStorm, IDEA, etc.), you'll need to click on CRLF/LF to toggle between the two types of line separators (\r\n and \n).
I was trying to startup my docker container from Windows and got this:
Bash script and /bin/bash^M: bad interpreter: No such file or directory
I was using git bash and the problem was about the git config, then I just did the steps below and it worked. It will configure Git to not convert line endings on checkout:
git config --global core.autocrlf input
delete your local repository
clone it again.
Many thanks to Jason Harmon in this link:
https://forums.docker.com/t/error-while-running-docker-code-in-powershell/34059/6
Before that, I tried this, that didn't works:
dos2unix scriptname.sh
sed -i -e 's/\r$//' scriptname.sh
sed -i -e 's/^M$//' scriptname.sh
If you're using the read command to read from a file (or pipe) that is (or might be) in DOS/Windows format, you can take advantage of the fact that read will trim whitespace from the beginning and ends of lines. If you tell it that carriage returns are whitespace (by adding them to the IFS variable), it'll trim them from the ends of lines.
In bash (or zsh or ksh), that means you'd replace this standard idiom:
IFS= read -r somevar # This will not trim CR
with this:
IFS=$'\r' read -r somevar # This *will* trim CR
(Note: the -r option isn't related to this, it's just usually a good idea to avoid mangling backslashes.)
If you're not using the IFS= prefix (e.g. because you want to split the data into fields), then you'd replace this:
read -r field1 field2 ... # This will not trim CR
with this:
IFS=$' \t\n\r' read -r field1 field2 ... # This *will* trim CR
If you're using a shell that doesn't support the $'...' quoting mode (e.g. dash, the default /bin/sh on some Linux distros), or your script even might be run with such a shell, then you need to get a little more complex:
cr="$(printf '\r')"
IFS="$cr" read -r somevar # Read trimming *only* CR
IFS="$IFS$cr" read -r field1 field2 ... # Read trimming CR and whitespace, and splitting fields
Note that normally, when you change IFS, you should put it back to normal as soon as possible to avoid weird side effects; but in all these cases, it's a prefix to the read command, so it only affects that one command and doesn't have to be reset afterward.
Coming from a duplicate, if the problem is that you have files whose names contain ^M at the end, you can rename them with
for f in *$'\r'; do
mv "$f" "${f%$'\r'}"
done
You properly want to fix whatever caused these files to have broken names in the first place (probably a script which created them should be dos2unixed and then rerun?) but sometimes this is not feasible.
The $'\r' syntax is Bash-specific; if you have a different shell, maybe you need to use some other notation. Perhaps see also Difference between sh and bash
Since VS Code is being used, we can see CRLF or LF in the bottom right depending on what's being used and if we click on it we can change between them (LF is being used in below example):
We can also use the "Change End of Line Sequence" command from the command pallet. Whatever's easier to remember since they're functionally the same.
One more way to get rid of the unwanted CR ('\r') character is to run the tr command, for example:
$ tr -d '\r' < dosScript.py > nixScript.py
I ran into this issue when I use git with WSL.
git has a feature where it changes the line-ending of files according to the OS you are using, on Windows it make sure the line endings are \r\n which is not compatible with Linux which uses only \n.
You can resolve this problem by adding a file name .gitattributes to your git root directory and add lines as following:
config/* text eol=lf
run.sh text eol=lf
In this example all files inside config directory will have only line-feed line ending and run.sh file as well.
For Notepad++ users, this can be solved by:
The simplest way on MAC / Linux - create a file using 'touch' command, open this file with VI or VIM editor, paste your code and save. This would automatically remove the windows characters.
If you are using a text editor like BBEdit you can do it at the status bar. There is a selection where you can switch.
For IntelliJ users, here is the solution for writing Linux script.
Use LF - Unix and masOS (\n)
Scripts may call each other.
An even better magic solution is to convert all scripts in the folder/subfolders:
find . -name "*.sh" -exec sed -i -e 's/\r$//' {} +
You can use dos2unix too but many servers do not have it installed by default.
For the sake of completeness, I'll point out another solution which can solve this problem permanently without the need to run dos2unix all the time:
sudo ln -s /bin/bash `printf 'bash\r'`
I was running the following command:
docker run -e 'SOME_ENV_VARIABLE=somevalue' somecommand
And this did not pass the env variable to somecommand (Note: SOME_ENV_VARIABLE and somevalue did not have un-escaped single quotes, they were capital snake case and lowercase respectively without special character.
Later, I tried:
docker run -e "SOME_ENV_VARIABLE=somevalue" somecommand
And this somehow worked (note the double quotes).
Why is this? I have seen documentation with single quotes.
I tried this on Windows.
Quotation is handled by your shell - since you are on windows, that is cmd.exe. And, from what I understand, since cmd.exe does not handle single quotes, it will pass that argument with the quotes to docker.
It would work on Linux though (which usually has the bash shell), being the the environment many people would use docker on, and as such the reason it is present in a lot of documentation.
I'm trying to create a script that starts a docker container and mounts a local folder that contains spaces in the name. I can get it to work fine when I run a *.bat file with the docker run command:
docker run -p 8081:8081 -v "C:\Test Folder With Blanks":/zzz myimage jupyter lab --notebook-dir=/zzz--ip=0.0.0.0 --port=8081 --allow-root
But when I try to do the same in a Powershell script file, I get an error:
$CMD = 'docker run -p 8081:8081 -v "C:\Test Folder With Blanks":/zzz myimage jupyter lab --notebook-dir=/zzz--ip=0.0.0.0 --port=8081 --allow-root'
Invoke-Expression $CMD
docker: invalid reference format.
See 'docker run --help'.
I'm on Win10 and running Powershell in Visual Studio Code IDE.
Thanks for ideas.
First, the obligatory warning: Unless you have a command line stored as a single string somewhere and you either fully control or trust the content of the string, Invoke-Expression should generally be avoided.
You're seeing an inconsistency in how PowerShell treats compound tokens composed of directly concatenated quoted and unquoted parts.
Specifically, argument "C:\Test Folder With Blanks":/zzz is unexpectedly broken in two, i.e passed as two arguments.
The workaround is to quote the entire argument, i.e.
"C:\Test Folder With Blanks:/zzz"
Note: I'm assuming that docker doesn't actually require partial quoting in its arguments, which it shouldn't; however, there are high-profile CLIs on Windows that do, notably msiexec.
Alternatively, use an expression enclosed in (...) to compose your string; e.g.
("C:\Test Folder With Blanks" + ':/zzz')
There's no good reason to do so in this case, but it could be helpful if you need string interpolation in one part of your string ("..."), but not in another ('...').
General caveats:
Compared to cmd.exe and also POSIX-compatible shells such as bash, PowerShell has several additional metacharacters, notably # (at the start of a token), { / }, and ;. Therefore, you cannot always expect command lines written for these shells to work as-is in PowerShell.
As of PowerShell 7.2.2, passing arguments to external programs (such as docker) is fundamentally broken with respect to arguments that have embedded " characters and empty-string arguments - see this answer.
The general pattern of the inconsistency, as of PowerShell 7.2.2, is as follows:
If an argument:
starts with a quoted token - whether single- ('...') or double-quoted ("...") -
and has additional characters directly following the closing quote,
the first such character starts a separate argument.
E.g. "foo":bar / "foo"=bar / "foo"'bar' are passed as separate arguments foo and :bar / foo and =bar / foo and bar, respectively.
In other words:
You cannot compose a single string argument from a mix of quoted and unquoted / differently quoted tokens if the first token is quoted.
Conversely, it does work if the first token is unquoted, including an unquoted simple variable reference such as $HOME.
# OK: First token is unquoted.
PS> cmd /c echo foo"bar"'baz'last
foobarbazlast
# !! BROKEN: First token is quoted.
# !! Because each successive token is quoted too,
# !! each becomes its own argument.
PS> cmd /c echo 'foo'"bar"'baz'last
foo bar baz last
GitHub issue #6467 discusses this inconsistency; however, it has been closed, because the behavior is - surprisingly - considered by design.
This does not happen if the first token is unquoted; however, there are related bugs that start with unquoted tokens that similarly break arguments in two, related to their looking like named arguments to PowerShell (which is a PowerShell concept that doesn't apply when calling external programs):
GitHub issue #11646: an argument such as -foo=1,2 breaks parsing.
GitHub issue #6291: an argument such as -foo=bar.baz is broken in two at the (first) .
I have a variable in my jboss cli file, let's call it ${FOO}.
I can see that the variable is set in my Dockerfile, if I:
RUN echo ${FOO}
I see the value printed.
I have a foo.cli file which contains a line similar to:
/system-property=foo:add(value="${FOO}")
and when I run jboss-cli.sh foo.cli
I get:
Cannot resolve expression ${FOO}.
Is there a way to pass a variable from Docker to the file argument to jboss-cli.sh ?
I've tried removing the quotes around ${FOO} also in the system-property line but no luck.
This is due to the fact that the CLI does not treat values the same as names. In short, operation names, parameter names, header names and values, command names as well as command argument names are resolved automatically. Parameter and argument values aren’t. To fix this, we need to set resolve-parameter-values to true in jboss-cli.xml.
For e.g.:-
sed -i "s/<resolve-parameter-values>false<\/resolve-parameter-values>/\
<resolve-parameter-values>true<\/resolve-parameter-values>/" \
$JBOSS_HOME/bin/jboss-cli.xml
Note that the command above is meant to be a one-off solution. From the maintenance perspective, using sed for XML is not a good idea in general. If you’re automating this, consider using XPath instead.
Note:- This functionality requires WildFly 8.0.0.CR1 or newer.
you might need to set jboss-cli.xml to <resolve-parameter-values>true<\/resolve-parameter-values>
$ sed -i "s/<resolve-parameter-values>false<\/resolve-parameter-values>/\
<resolve-parameter-values>true<\/resolve-parameter-values>/" \
$JBOSS_HOME/bin/jboss-cli.xml
src: https://mirocupak.com/using-environment-variables-in-jboss-cli/
These are good hints how to solve the problem, but the sed command does not work this way on Mac. There is a lot of fun with "-i". More information here:
sed command with -i option failing on Mac, but works on Linux
On Mac this worked for me:
sed -i "" "s/false</resolve-parameter-values>/true</resolve-parameter-values>/" $JBOSS_HOME/bin/jboss-cli.xml
Unfortunately this way of using sed does not work on RHEL for example.
I am running an ant command from Cygwin terminal where I am signing my exe.
I am running a command similar to
ant -Dpassword=$abcde
Here $abcde is my password but when I run an echo, it shows the password as blank.
How can I pass $ as part of my argument so ant can process it?
In a Unix shell, the $ sign is used to identify a shell variable. To prevent parameter expansion due to it being treated as a variable, you need to either:
escape it (by prepending a backslash)
or wrap it in single quotes (quoting removes the special meaning of certain characters such as $)
Either of the following should work:
ant -Dpassword=\$abcde
ant -Dpassword='$abcde'
Edit: It seems that ant treats the dollar sign as a special character. Assuming that a backslash can be used by ant for escaping special characters, both the backslash and the dollar character should be passed on to ant by the shell:
ant -Dpassword='\$abcde'