I have a bash script .sh which needs to be executed as a Target Simulator in Eclipse. The problem is, if I run the script with sh run.sh command in terminal, it throws Bad Substitution error. But it works perfectly with bash run.sh. Apparently, Eclipse run it with sh command cause it gives the same error in console. But how can I make Eclipse to run the script with bash instead?
I'm on Ubuntu 13.10.
bash and sh aren't the same shell. There are many constructs valid in bash that are not understood by sh.
Have you provided a correct sheebang as the first line of your script?
#!/bin/bash
If so -- and if Eclipse insist on running script with sh, you still have the option of wrap your script in a heredoc and pass it to bash explicitly:
sh$ cat run.sh
bash << EOF
#
# Here is your bash script
#
EOF
This is mostly a hack until you find how to instruct Eclipse of using the right shell. I'm sure there is a way!
Related
I want to run this script:
#!/bin/bash
echo <(true)
I run it as:
sh file.sh
And I get "Syntax error: "(" unexpected" . I found some similar situations but still can't solve this.
I'm a beginner at shell scripting , but as I understand:
the shebang I use is correct and chooses the bash shell , so the process substitution syntax should work
I try the same from the command line and it works. I checked with echo $0 and it gives me "bash" , so what's the difference from running the command in the command line and from a script that invokes the same shell?
Maybe it's something simple, but I couldn't find an explanation or solution.
You should run your script with bash, i.e. either bash ./script.sh or making use of the shebang by ./script.sh after setting it to executable. Only running it with sh ./script.sh do I get your error, as commented by Cyrus.
See also: role of shebang at unix.SE
Remove export POSIXLY_CORRECT=1 from your ~/.bashrc or ~/.profile (etc.) files.
The issue is that process substitution is an added bash feature that is not part of the posix standards.
sh file.sh
errorsh: 3: Syntax error: "(" unexpected
solution:
bash file.sh
I am trying to play with bash and arrays. But executing a sample script, I got an unexpected syntax error message: example.sh: 3: example.sh: Syntax error: "(" unexpected. And this is the script
#!/bin/bash
array=( one two three )
If I run the script with ./example.sh it works and no errors are displayed. But if I run sh example.sh I get the error message.
I thought that these two commands are the same:
sh example.sh
./example.sh
so ... what is the difference between the two?
When you launch it via ./example.sh then the command specified in the first line of the script is used to interpret the content. So your script executes in a bash, where such syntax is allowed for arrays.
When you launch it via sh example.sh then sh is the command that is used to interpret the content of the file. sh is the original Unix shell (aka Bourne shell) and this shell is a little more rude than bash (Bourne again shell). You don't have such arrays. Note that in sh the first line of your script is just interpreted as a comment.
by using sh example.sh
- you are specifying what shell interpreter to use for that script. Example being "bash example.sh" instead of "sh example.sh" etc etc.
Running scripts this way disregards the "shebang (#!/bin/bash)" that you have specified inside of the script. Since you wrote a bash script but are trying to run it as just "sh", this is why it is failing
by using ./example.sh,
- You are specifying to run the script from your current directory. This will attempt to run the script in whatever shell you are currently in unless a shebang is specified. Since you have a "shebang" specified to run the script in bash... this is why it is working.
array_name=(value1 ... valuen)
This is how to initializes an array in bash only. When you execute ./example.sh, the shebang line #!/bin/bash tells the system to use bash to execute.
However, when you execute sh example.sh, sh is used to execute. In many Unix systems (like Linux), sh is equivalent to bash. It seems sh is a different shell on your system.
I have some shell scripts which I run in my Linux/AIX machine with bash profile. Now my bash profile is going to be remove, and I will have Korn shell (ksh) or the C shell (csh). How to verify whether my scripts will run fine in Korn shell (ksh) or C shell (csh), even after bash shell is removed. Also, is there any differnce in commonly used commands between bash and other (ksh, csh). Is there command to check, which shell is getting used while running the shell script.
First of all, this is not a problem, the default shell of your account is irrelevant. As long as bash is installed on the machine, you can use it to run your code. Either add a shebang line as the first line of your script:
#!/usr/bin/env bash
Or, explicitly run the script with bash:
$ /bin/bash /path/to/script.sh
As for the differences, yes there are many. A script written for bash will not run in csh, their syntax is completely different. It might run on ksh but that will depend on your script. Not all features of the two shells are the same. For example:
$ cat test.sh
var="foo";
echo $var;
$ bash ./test.sh
foo
$ ksh ./test.sh
foo
$ csh ./test.sh
var=foo: Command not found.
var: Undefined variable.
As you can see above, var=foo runs correctly in ksh (which is part of the bourne shell family) but fails for csh. Basically, think of each shell as its own programming language. You wouldn't expect the python interpreter to be able to run a perl program, why do you expect one shell to be able to run a script written for another?
OP writes bash is going to be removed.
If you really cannot get bash installed. start each script with #!/bin/ksh and check for syntax problems:
ksh -n migrated_script
When you use bash/linux specific things you need to address them:
AIX will be "missing" flags on commands like find (changed last hour...) and ksh itself is also different.
Do not try csh, that is completely different.
I have one script which runs in Bash and and other which runs in tcsh.
I need to run them both from the same script. How can I create a script that
can run both bash and tcsh commands?
Most shells have an argument which allow you to pass them a string to run as a command, for example, for bash you can run
bash -c "echo this is a bash script; echo lalalala"
to run that string as a script in bash, use this to run the needed shell embedded in the other. This will allow you to make a script in one shell which will invoke the other shell when the other program needs to be run.
If on the other hand they are both properly shebanged begin with #!tcsh or #!bash you can simply run both scripts from the same bash script using:
/path/to/script1 &
/path/to/script2 &
I have a shell script file (run.sh) that contains the following:
#!/bin/bash
%JAVA_HOME%/bin/java -jar umar.jar
when i try to run it (./run.sh), it gives me following:
umar/bin/run.sh: line 1: fg: no job control
However if I run same command directly on shell, it works perfectly.
What's wrong with the script file?
Thanks
%foo% is not how you do command substitution in a bourne/BASH shell script. I assume you're running this from a Windows command line, which is why it works when you run it directly. Try using proper bourne syntax:
${JAVA_HOME}/bin/java -jar umar.jar
Try turning on monitor mode
set -m
%JAVA_HOME% will substitute a Windows environment variable and is appropriate in a .bat file.
Try the following shell script which should work on most UNIX like systems.
#!/bin/bash
$JAVA_HOME/bin/java -jar umar.jar