I'm creating a script like this
#!/bin/csh
set h=1;
while [h=1] do echo "hi"; h=2; done;
but when I execute it a get this:
===> message after : csh test.sh [h=1]: No match.
Try:
set h = 1
while ( $h == 1 )
echo "hi"
set h = 2
end
You seem to be trying to mix Bourne shell syntax into your C shell script.
Csh is generally a lousy language for scripting, try to avoid it if at all possible
http://www.faqs.org/faqs/unix-faq/shell/csh-whynot/
UPDATE:
The csh equivalent to read h is:
set h = $<
Related
One thing that's really great in linux bash shell is that you can define variables inside of a subshell and after that subshell completes the (environment?) variables defined within are just gone provided you define them without exporting them and within the subshell.
for example:
$ (set bob=4)
$ echo $bob
$
No variable exists so no output.
I was also recently writing some powershell scripts and noticed that I kept having to null out my variables / objects at the end of the script; using a subshell equivalent in powershell would clear this up.
I've not heard of such functionality before, but you can get the same effect by running something like the following:
Clear-Host
$x = 3
& {
$a = 5
"inner a = $a"
"inner x = $x"
$x++
"inner x increment = $x"
}
"outer a = $a"
"outer x = $x"
Output:
inner a = 5
inner x = 3
inner x increment = 4
outer a =
outer x = 3
i.e. this uses the call operator (&) to run a script block ({...}).
I want all variables names are set in shell script. I have a file which contains key value pairs and I was read content from that file and store/set into variables. I want to do some processes if a variable is available/set otherwise I don't need to do those processes. How to achieve this.
For example I run loop in shell scripts in each iteration it gives one of the variables is set before that command.
If code like this
a=test1
b=test2
c=test3
for i in ???
do
echo $i
done
then I want output like this
a
b
c
What command is used o achieve this.
You could use set before and after setting the variables
e.g:
$ set > aux1
$ c=345
$ set > aux2
$ diff aux1 aux2
57c57
< PIPESTATUS=([0]="141" [1]="0")
---
> PIPESTATUS=([0]="0")
112a113
> c=345
If you have a pre-defined list of such variables, then you can test it like this:
for i in $(echo "a b c"); do
echo $i
done
If i could help you :
#!/bin/sh
# Define list of tests
LIST_TESTS=`cat list_test.txt`
for TEST in ${LIST_TESTS}
do
vartest=`echo ${TEST}`
if [ "${vartest}" = "" ]
# No Test
then
echo "*** WARNING*** Test not found"
else
echo "${vartest} is available"
fi
done
# Second Define list of tests
tabTest=('test1' 'test2' 'test3')
i=0
while [ "${tabTest[$i]}" != "" ]
do
echo "${tabTest[$i]} is available"
i=$(($i+1))
done
I need to convert a string value to integer in c shell. I am passing a string variable from Python to c shell script and in c shell in need to change it to integer. The variable I am passing is say br ="2" but in c shell in need to change it to integer 2.
Any solution that allows me to pass an integer value from python to c shell will also help.
import subprocess
import shlex
var = "nest"
env_var = "16"
script = "./testshell.csh"
#prepare a command (append variable to the scriptname)
command = "{} {}".format(script, var)
#prepare environment variables
environment = {"test_var" : env_var}
#Note: shlex.split splits a textual command into a list suited for subprocess.call
subprocess.call( shlex.split(command), env = environment )
This is the test shell script
#!/bin/csh
set br = $test_var
# nvar = br + 1
echo $nvar
Error is: #: Expression Syntax.
The problem is that you forgot to prefix br with a dollar sign ($), it should be:
# nvar = $br + 1
Example:
% set br = '2'
% # nvar = $br + 1
% echo $nvar
3
I am writing a csh alias so that I can use the following bash function in my csh :
function up( )
{
LIMIT=$1
P=$PWD
for ((i=1; i <= LIMIT; i++))
do
P=$P/..
done
cd $P
export MPWD=$P
}
(I stole the above bash function from here)
I have written this:
alias up 'set LIMIT=$1; set P=$PWD; set counter = LIMIT; while[counter!=0] set counter = counter-1; P=$P/.. ; end cd $P; setenv MPWD=$P'
However, I am getting the following error:
while[counter!=0]: No match.
P=/net/devstorage/home/rghosh/..: Command not found.
end: Too many arguments.
and my script is not working as intended. I have been reading up on csh from here.
I am not an expert in csh and what I have written above is my first csh script. Please let me know what I am doing wrong.
You can also do this
alias up 'cd `yes ".." | head -n\!* | tr "\n" "\/"`'
yes ".." will repeat the string .. indefinitely; head will truncate it to the number passed as argument while calling the alias ( !* expands to the arguments passed; similar to $# ) and tr will convert the newlines to /.
radical7's answer seems to be more neat; but will only work for tcsh ( exactly wat you wanted ). This should work irrespective of the shell
You can use the csh's repeat function
alias up 'cd `pwd``repeat \!^ echo -n /..`'
No loops needed (which is handy, because while constructs in tcsh seem very finicky)
For multiple lines of code, aliases must be within single quotes, and each end of line must precede a backslash. The end of the last line must precede a single quote to delimit the end of the alias:
alias up 'set counter = $1\
set p = $cwd\
while $counter != 0\
# counter = $counter - 1\
set p = $p/..\
end\
cd $p\
setenv mpwd $p'
By the way, variables set with set are better with the equal sign separated from the variable name and content; setenv doesn't require an equal sign; math functionality is provided by #; control structures make use of parentheses (though aren't required for simple tests); use $cwd to print the current working directory.
In the bash manual section 3.7.4, it states
The environment for any simple command or function may be augmented
temporarily by prefixing it with parameter assignments, as described
in Shell Parameters [section 3.4].
And a trivial example of this is
MYVAR=MYVALUE mycommand
I have read section 3.4 and I still can't figure out how to specify multiple parameter assignments. Note that the statement in 3.7.4 is definitely plural, implying that it is possible.
The following does not seem to work:
MYVAR1=abc MYVAR2=xyz mycommand
I am using bash version 4.1, 23 December 2009.
It should work. That is acceptable syntax. Here's an example:
$ cat a
#!/bin/sh
echo $MYVAR1
echo $MYVAR2
$ ./a
$ MYVAR1=abc MYVAR2=xyz ./a
abc
xyz
$
UPDATE: Your updated example given in your answer will work if you precede the simple command with the variables as required:
mycommand () { echo MYVAR1=[$MYVAR1]; echo MYVAR2=[$MYVAR2]; }
for f in ~/*.txt ; do MYVAR1=abc MYVAR2=xyz mycommand; done
Oops, my example was over-simplified. This works fine:
mycommand () { echo MYVAR1=[$MYVAR1]; echo MYVAR2=[$MYVAR2]; }
MYVAR1=abc MYVAR2=xyz mycommand
but this does not:
mycommand () { echo MYVAR1=[$MYVAR1]; echo MYVAR2=[$MYVAR2]; }
MYVAR1=abc MYVAR2=xyz for f in ~/*.txt; do mycommand; done
and the key difference is this phrase:
for any simple command or function
A for command is a complex command, not "a simple command or function", according to section 3.2.
I've never seen that method used.
You could always just pass in regular parameters to the script.
Updating for new example:
This works in both situations:
> mycommand () { echo MYVAR1=[$1]; echo MYVAR2=[$2]; }
> mycommand a b
MYVAR1=[a]
MYVAR2=[b]
> for f in ~/file*.txt; do mycommand a b; done
MYVAR1=[a]
MYVAR2=[b]
MYVAR1=[a]
MYVAR2=[b]