Run cd in script and stay in that directory - 'source' command not helping - unix

Tried using the answer found here:
How to run 'cd' in shell script and stay there after script finishes?
When I add the 'source' command, the directory is still unchanged after script runs, regardless of whether I execute 'source ' or call the script using an alias coded in cshrc.
Any help is much appreciated!

As you can see below, make sure your call to cd is not executing within a subshell. If it is, this won't work, source or not.
Script with cd in subshell
#!/bin/bash
( cd /etc ) # thie exec's in a subshell
Output
$ pwd
/home/siegex
$ source ./cdafterend.sh && pwd
/home/siegex
Script with cd not in subshell
#!/bin/bash
cd /etc # no subshell here
Output
$ pwd
/home/siegex
$ source ./cdafterend.sh && pwd
/etc

It was necessary to remove "/bin/" from the cd command within this script, in order for the command to work as intended. Removing this removes the subshell issue for this script. Also, coding "$1" in the ls command was invalid in this context.

Related

Unable to export env variable from script

I'm currently struggling with running a .sh script I'm trying to trigger from Jenkins.
Within the Jenkins "execute shell" section, I'm connecting to a remote server (The Jenkins agent does not have right OS to build what I need.), using:
cp -r . /to/shared/drive/to/have/access/on/remote
ssh -t -t username#servername << EOF
cd /to/shared/drive/to/have/access/on/remote
source build.sh dev
exit
EOF
Inside build.sh, I'm exporting R_LIBS to build a package for different R versions.
...
for path in "${!rVersionPaths[#]}"; do
export R_LIBS="${path}"
Rscript -e 'install.packages(c("someDependency", "someOtherDependency"), repos="http://cran.r-project.org");'
...
Setting R_LIBS should functions here like setting lib within install.packages(...). For some reason the R_LIBS export doesn't get picked up. Also setting other env variables like http_proxy are ignored. This causes any requests outside the network to fail.
Is there any particular way of achieving this?
Maybe pass those variables with env, like
env R_LIBS="${path}" Rscript -e 'install.packages(c("someDependency", .....
Well i'm not able to comment on the question, so posting it as answer.
I had similar problem when calling remote shell script from Jenkins, the problem was somehow bash_profile variables were not loaded when called the script from Jenkins but locally it worked. Loading the bash profile in ssh connection solved it for me.
Add source to bash_profile in build.sh
. ~/.bash_profile OR source ~/.bash_profile
Or
Reload bash_profile in ssh connection
`ssh -t -t username#servername << EOF
. ~/.bash_profile
your commands here
exit
EOF
You can set that variable in the same command line like this:
R_LIBS="${path}" Rscript -e \
'install.packages(c("someDependency", "someOtherDependency"), repos="http://cran.r-project.org");'
It's possible to append more variables in this way. Note that this will set those environment variables only for the command being called after them (and its children processes as well).
You said that "R_LIBS export doesn't get picked up". Question Is the value UNSET? Or is it set to some other value & you are trying to override it?
It is possible that SSH may be invoking "/bin/sh -c". Based on the second answer to: Why does 'cd' command not work via SSH?, you can simplify the SSH command and explicitly invoke the build.sh script in Bash:
cp -r . /to/shared/drive/to/have/access/on/remote
ssh -t -t username#servername "cd /to/shared/drive/to/have/access/on/remote && bash -f build.sh dev"
This makes the SSH invocation more similar to invoking the command within a remote interactive shell. (You can avoid sourcing scripts and exporting variables.)
You don't need to export R_LIBSor env R_LIBS when it is possible to prefix any command with local environment variable overrides (agrees with Luis' answer):
...
for path in "${!rVersionPaths[#]}"; do
R_LIBS="${path}" Rscript -e 'install.packages(c("someDependency", "someOtherDependency"), repos="http://cran.r-project.org");'
...
The Rscript may be doing a lot with env vars. You can verify that you are setting the R_LIBS env var by replacing Rscript with the env command and observe the output:
...
for path in "${!rVersionPaths[#]}"; do
R_LIBS="${path}" env
...
According to this manual "Initialization at Start of an R Session", Rscript looks in several places to load "site and user files":
$R_PROFILE
$R_HOME/etc/Renviron
$R_HOME/etc/Renviron.site
$R_ENVIRON_USER
$R_PROFILE_USER
./.Rprofile
$HOME/.Rprofile
./.RData
The "Examples" section of that manual shows this:
## Not run:
## Example ~/.Renviron on Unix
R_LIBS=~/R/library
PAGER=/usr/local/bin/less
If you add the --vanilla command-line option to ignore all of these files, then you may get different results and know something in the site/init/environ files is affecting your R_LIBS! I cannot run this system myself. Hopefully we have given you some areas to investigate.
You probably don't want to source build.sh, just invoke it directly (i.e. remove the source command).
By source-ing the file your script is executed in the SSH shell (likely sh) rather than by bash, which it sounds like is what you intended.

Unix script changing directory

I am in root directory, i am creating a script that will take me from root > Home > Logs and inside logs delete 3 log files.
Script will check if they exist, if YES it will delete it.
I am facing some syntax problems if you could help.
Thanks
My code:
#!/bin/sh
cd Home/Log
if [ -e error1.log ]
then
rm error1
fi
if [ -e error2.log ]
then
rm error1
fi
if [ -e error3.log ]
then
rm error1
fi
when i execute the file in root using ./delete here is what is am getting as errors:
$ ./delete
: No such file or directoryme/Log
./delete: line 14: syntax error near unexpected token `fi'
I am in root directory
When writing a script, it's almost always better not to assume things like that. If you know where the files are and it's not important that they're somewhere relative to what happens to be your current working directory, just name them.
Here are three ways you could accomplish what you want safely.
#!/bin/sh
dir=/Home/Log
rm -f ${dir}/error1.log ${dir}/error2.log ${dir}/error2.log
or
#!/bin/sh
dir=/Home/Log
rm -f ${dir}/error{1,2,3}.log
or
#!/bin/sh
set -e
cd /Home/Log && rm -f error1.log error2.log error2.log
For anything nontrivial, set -e is your friend. In your example, nothing happens later in the script. What you don't want is to keep going thinking you've changed directories, but haven't, and wind up scribbling somewhere you didn't intend. Many have lost much that way.

How to always have the same current directory in VIm and in Terminal?

I would like to my terminal current directory follows my VIM one.
Example:
In TERMINAL:
> pwd
=> /Users/rege
> vim
Then in VIM
:cd /Users/rege/project
<Ctrl-z>(for suspend)
In terminal
> pwd
=> /Users/rege/project
I`m using MacOS, zsh, tmux.
I need this because when Im trying to use tags in VIM, tags are check in project from my terminal directory not vim one.
So I need to change terminal current directory always when I change VIM current directory.
What kind of command do you issue in your shell after you suspend Vim? Isn't Vim's :!command enough?
With set autochdir, Vim's current directory follows you as you jump from file to file. With this setting, a simple :!ctags -R . will always create a tags file in the directory of the current file.
Another useful setting is set tags=./tags,tags;$HOME which tells Vim to look for a tags file in the directory of the current file, then in the "current directory" and up and up until it reaches your ~/. You might modify the endpoint to suit your needs. This allows you to use a tags at the root of your project while editing any file belonging to the project.
So, basically, you can go a long way without leaving Vim at all.
If you really need to go back to the shell to issue your commands, :shell (or :sh) launchs a new shell with Vim's current directory. When you are done, you only have to $ exit to go back to Vim:
$ pwd
/home/romainl
$ vim
:cd Projects
:sh
$ pwd
/home/romainl/Projects
$ exit
In bash or zsh and on Unix you can do this: current working directory of the process is represented in /proc/{PID}/cwd as a symlink to a real directory. Speaking about zsh the following code will do the job:
function precmd()
{
emulate -L zsh
(( $#jobstates == 1 )) || return
local -i PID=${${${(s.:.)${(v)jobstates[1]}}[3]}%\=*}
cd $(readlink /proc/$PID/cwd)
}
. Note: with this code you won’t be able to pernamently switch directories in terminal anymore, only in vim or for duration of one command (using cd other-dir && some command).
Note 2: I have no idea how to express this in bash. The straightforward way is to get PIDs of all children of the shell (using ps --ppid $$ -o CMD), filter out the ps process (it will be shown as a child as well), check that there is only one other child and use its PID like in the last line above. But I am pretty sure there is a better way using some shell builtins like I did with zsh’s $jobstates associative array. I also don’t remember what is the analogue of precmd in bash.
Another idea would be making vim save its current directory into some file when you do <C-z> and make shell read this in precmd:
" In .vimrc:
function s:CtrlZ()
call writefile([fnamemodify('.', ':p')], $CWDFILE, 'b')
return "\<C-z>"
endfunction
nnoremap <expr> <C-z> <SID>CtrlZ()
# In .zshrc
function vim()
{
local -x CWDFILE=~/.workdirs/$$
test -d $CWDFILE:h || mkdir $CWDFILE:h
vim $#
}
function precmd()
{
local CWDFILE=~/.workdirs/$$
test -e $CWDFILE && cd "$(cat $CWDFILE)"
}
. It should be easier to port above code to bash.
you can open a new terminal like this
:!xterm -e bash -c "cd %:p:h;bash" &
actually I write this in my .vimrc
nmap <F3> :!xterm -e bash -c "cd %:p:h;bash" &<CR> | :redraw!
For bash users coming by:
Vim: Save pwd at <c-z> (with map and getpwd()).
Bash: Before prompt command, goto directory indicated by vim with PROMPT_COMMAND.
.bashrc
PROMPT_COMMAND='read -r line 2>/dev/null </tmp/cd_vim'\
'&& > /tmp/cd_vim && cd ${line##\r};'$PROMPT_COMMAND
vimrc
function! s:CtrlZ() call writefile([getcwd(),''], '/tmp/cd_vim', 'b')
return "\<C-z>"
endfunction
nnoremap <expr> <C-z> <SID>CtrlZ()
This is ZyX answer edited for bash https://stackoverflow.com/a/12241861/2544873

How can invoke a shell to make a new environment to run a make inside another make?

I would like in my GNUmakefile to have a target rule that invokes a new shell and then with the clean slate of the new shell invokes a new make.
What is the syntax to do this?
I tried this but it didn't work:
.PHONY: setup
setup:
shell cd myDir; make; cd ..
It gets infinite repeat of the following error:
make[1]: Entering directory `/disk4/home/user/parent'
shell cd myDir; make; cd ..
/bin/sh: shell: command not found
make[1]: Entering directory `/disk4/home/user/parent'
shell cd myDir; make; cd ..
/bin/sh: shell: command not found
[...]
(cd myDir ; make)
The parens invoke a new subshell, with its own "current directory".
The parens are not necessary. Every line in a recipe is invoked in its own shell anyway. Your recipe seems to have a superfluous shell string, which your shell tries to execute as a command (/bin/sh (your shell, not make) complains shell: command not found).
Also, make's -C parameter is handy in this case.
Also, when calling make from the shell, use the ${MAKE} macro.
.PHONY: setup
setup:
unset MAKEFLAGS; ${MAKE} -C myDir
Here is what works:
.PHONY: setup
setup:
(cd myDir; env --unset=MAKEFLAGS make)

Whats the difference between running a shell script as ./script.sh and sh script.sh

I have a script that looks like this
#!/bin/bash
function something() {
echo "hello world!!"
}
something | tee logfile
I have set the execute permission on this file and when I try running the file like this
$./script.sh
it runs perfectly fine, but when I run it on the command line like this
$sh script.sh
It throws up an error. Why does this happen and what are the ways in which I can fix this.
Running it as ./script.sh will make the kernel read the first line (the shebang), and then invoke bash to interpret the script. Running it as sh script.sh uses whatever shell your system defaults sh to (on Ubuntu this is Dash, which is sh-compatible, but doesn't support some of the extra features of Bash).
You can fix it by invoking it as bash script.sh, or if it's your machine you can change /bin/sh to be bash and not whatever it is currently (usually just by symlinking it - rm /bin/sh && ln -s /bin/bash /bin/sh). Or you can just use ./script.sh instead if that's already working ;)
If your shell is indeed dash and you want to modify the script to be compatible, https://wiki.ubuntu.com/DashAsBinSh has a helpful guide to the differences. In your sample it looks like you'd just have to remove the function keyword.
if your script is at your present working directory and you issue ./script.sh, the kernel will read the shebang (first line) and execute the shell interpreter that is defined. you can also call your script.sh by specifying the path of the interpreter eg
/bin/bash myscript.sh
/bin/sh myscript.sh
/bin/ksh myscript.sh etc
By the way, you can also put your shebang like this (if you don't want to specify full path)
#!/usr/bin/env sh
sh script.sh forces the script to be executed within the sh - shell.
while simply starting it from command line uses the shell-environemnt you're in.
Please post the error message for further answers.
Random though on what the error may be:
path specified in first line /bin/bash is wrong -- maybe bash is not installed?

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