How Can I prevent duplicate change text file in linux? - linux

I have successfully changed text in linux using this shell script
vi -e .bash_profile << END
i
PATH=\$PATH:\$HOME/bin:/usr/pgsql-9.4/bin
export PATH
PGDATA=/usr/pgsql-9.4/data
export PGDATA
.
w
q
END
but I have a problem.
If I execute script twice then duplicate in text file.
So, I want to prevent this situation. How Can I fix it?

Well that depends... if the string "PATH=$PATH:$HOME/bin:/usr/pgsql-9.4/bin" can appear at other places in side the file then we could not use it as an indicator that your vi has already done its work. But if the string otherwise does not appear we could wrap the whole thing
grep -q 'PATH=[$]PATH:[$]HOME/bin:/usr/pgsql-9.4/bin' .bash_profile
if [ $? -eq 1 ]
then
# do your vi stuff here
fi
You might replace the if stuff by
test $? -eq 0 && exit 0
if you were not going to do anything after the vi stuff

Related

One liner to append a file into another file but only if it hasn't already been added

I have an automated process that has a number of lines like the following pattern:
sudo cat /some/path/to/a/file >> /some/other/file
I'd like to transform that into a one liner that will only append to /some/other/file if /some/path/to/a/file has not already been added.
Edit
It's clear I need some examples here.
example 1: Updating a .bashrc script for a specific login
example 2: Creating a .screenrc for different logins
example 3: Appending to the end of a /etc/ config file
Some other caveats. The text is going to be added in a block (>>). Consequently, it should be relatively straight forward to see if the entire code block is added or not near the end of a file. I am trying to come up with a simple method for determining whether or not the file has already been appended to the original.
Thanks!
Example python script...
def check_for_appended(new_file, original_file):
""" Checks original_file to see if it has the contents of new_file """
new_lines = reversed(new_file.split("\n"))
original_lines = reversed(original_file.split("\n"))
appended = None
for new_line, orig_line in zip(new_lines, original_lines):
if new_line != orig_line:
appended = False
break
else:
appended = True
return appended
Maybe this will get you started - this GNU awk script:
gawk -v RS='^$' 'NR==FNR{f1=$0;next} {print (index($0,f1) ? "present" : "absent")}' file1 file2
will tell you if the contents of "file1" are present in "file2". It cannot tell you why, e.g. because you previously concatenated file1 onto the end of file2.
Is that all you need? If not update your question to clarify/explain.
Here's a technique to see if a file contains another file
contains_file_in_file() {
local small=$1
local big=$2
awk -v RS="" '{small=$0; getline; exit !index($0, small)}' "$small" "$big"
}
if ! contains_file_in_file /some/path/to/a/file /some/other/file; then
sudo cat /some/path/to/a/file >> /some/other/file
fi
EDIT: Op just told me in the comments that the files he wants to concatenate are bash scripts -- this brings us back to the good ole C preprocessor include guard tactics:
prepend every file with
if [ -z "$__<filename>__" ]; then __<filename>__=1; else
(of course replacing <filename> with the name of the file) and at the end
fi
this way, you surround the script in each file with a test for something that's only true once.
Does this work for you?
sudo (set -o noclobber; date > /tmp/testfile)
noclobber prevents overwriting an existing file.
I think it doesn't, since you wrote you want to append something but this technique might help.
When the appending all occurs in one script, then use a flag:
if [ -z "${appended_the_file}" ]; then
cat /some/path/to/a/file >> /some/other/file
appended_the_file="Yes I have done it except for permission/right issues"
fi
I would continue into writing a function appendOnce { .. }, with the content above. If you really want an ugly oneliner (ugly: pain for the eye and colleague):
test -z "${ugly}" && cat /some/path/to/a/file >> /some/other/file && ugly="dirt"
Combining this with sudo:
test -z "${ugly}" && sudo "cat /some/path/to/a/file >> /some/other/file" && ugly="dirt"
It appears that what you want is a collection of script segments which can be run as a unit. Your approach -- making them into a single file -- is hard to maintain and subject to a variety of race conditions, making its implementation tricky.
A far simpler approach, similar to that used by most modern Linux distributions, is to create a directory of scripts, say ~/.bashrc.d and keep each chunk as an individual file in that directory.
The driver (which replaces the concatenation of all those files) just runs the scripts in the directory one at a time:
if [[ -d ~/.bashrc.d ]]; then
for f in ~/.bashrc.d/*; do
if [[ -f "$f" ]]; then
source "$f"
fi
done
fi
To add a file from a skeleton directory, just make a new symlink.
add_fragment() {
if [[ -f "$FRAGMENT_SKELETON/$1" ]]; then
# The following will silently fail if the symlink already
# exists. If you wanted to report that, you could add || echo...
ln -s "$FRAGMENT_SKELETON/$1" "~/.bashrc.d/$1" 2>>/dev/null
else
echo "Not a valid fragment name: '$1'"
exit 1
fi
}
Of course, it is possible to effectively index the files by contents rather than by name. But in most cases, indexing by name will work better, because it is robust against editing the script fragment. If you used content checks (md5sum, for example), you would run the risk of having an old and a new version of the same fragment, both active, and without an obvious way to remove the old one.
But it should be straight-forward to adapt the above structure to whatever requirements and constraints you might have.
For example, if symlinks are not possible (because the skeleton and the instance do not share a filesystem, for example), then you can copy the files instead. You might want to avoid the copy if the file is already present and has the same content, but that's just for efficiency and it might not be very important if the script fragments are small. Alternatively, you could use rsync to keep the skeleton and the instance(s) in sync with each other; that would be a very reliable and low-maintenance solution.

Understand when to use spaces in bash scripts

I wanted to run a simple bash timer and found this online (user brent7890)
#!/usr/bin/bash
timer=60
until [ "$timer" = 0 ]
do
clear
echo "$timer"
timer=`expr $timer - 1`
sleep 1
done
echo "-------Time to go home--------"
I couldn't copy and paste this code because the server is on another network. I typed it like this (below) and got an error on the line that starts with "until".
#!/usr/bin/bash
timer=60
#Note I forgot the space between [ and "
until ["$timer" = 0 ]
do
clear
echo "$timer"
timer=`expr $timer - 1`
sleep 1
done
echo "-------Time to go home--------"
Where is spacing like this documented? It seems strange that it matters. Bash scripts can be confusing, I want to understand why the space is important.
There are several rules, two basic of that are these:
You must separate all arguments of a command with spaces.
You must separate a command and the argument, that follows after, with a space.
[ here is a command (test).
If you write ["$timer" that means that you start command [60,
and that is, of course, incorrect. The name of the command is [.
The name of the command is always separated from the rest of the command line with a space. (you can have a command with a space in it, but in this case you must write the name of the command in "" or '').

Making Sublime Text 2 command on linux behave as it does on MacOS X

There are many questions asking about accessing the Sublime Text 2 editor from the command line. The responses, in summary, are to make a symlink, alias or simple shell script to run the appropriate sublime_text command. I can do that. What I want is to make the linux version behave like the MacOS version.
On MacOS, I have the following:
ln -s /Applications/Sublime\ Text\ 2.app/Contents/SharedSupport/bin/subl ~/bin/subl
Then in my .zshrc:
alias subl="$HOME/bin/subl -n"
export EDITOR="$HOME/bin/subl -n -w"
This does two things. It gives me a subl command that opens any files given on the command line in a new window. The subl command does not block the terminal. It also sets up my editor to open sublime text to edit the arguments, but this time it does block. In particular, $EDITOR blocks until its arguments are closed. It does not block on unrelated sublime text windows.
I can achieve a similar effect on linux with the following:
In ~/bin/subl:
#! /bin/zsh
$HOME/Sublime\ Text\ 2/sublime_text -n $# &
and then in ~/bin/subl_wait: (think mate_wait for TextMate users)
#! /bin/zsh
exec $HOME/Sublime\ Text\ 2/sublime_text -n -w $#
I can then set EDITOR to subl_wait, and things almost work. subl opens files for editing and doesn't block. subl_wait opens files for editing and does block.
The problem is that subl_wait is waiting until all open files are closed, not just its arguments.
Is it possible to get this working perfectly?
Looks like I've found the issue. (Thanks to this post: http://www.sublimetext.com/forum/viewtopic.php?f=2&t=7003 )
Basic point: sublime behaves differently depending upon whether an instance is already running!
If an instance is already running then sublime on linux behaves similarly to MacOS. If no instance is running then the terminal blocks until you exit sublime.
With that in mind, we just need to modify the scripts to make sure sublime is running:
in ~/bin/subl_start:
#! /bin/zsh
if [ ! "$(pidof sublime_text)" ] ; then
# start sublime text main instance
# echo "Starting Sublime Text 2"
$HOME/Sublime\ Text\ 2/sublime_text &
sleep 1 # needed to avoid a race condition
fi
in ~/bin/subl:
#! /bin/zsh
. $HOME/bin/subl_start
exec $HOME/Sublime\ Text\ 2/sublime_text -n $#
in ~/bin/subl_wait:
#! /bin/zsh
. $HOME/bin/subl_start
exec $HOME/Sublime\ Text\ 2/sublime_text -n -w $#
Note that I've used the -n flags everywhere. This might not be your cup of tea. If you are using -n then you possibly also want to look at your close_windows_when_empty setting.
Inspired by the OP's answer, I've created a bash wrapper script for Sublime Text that incorporates all your findings and runs on both OSX and Linux.
Its purpose is threefold:
provide a unified subl CLI that works like ST's own subl on OSX: invoke ST without blocking, unless waiting is explicitly requested.
encapsulate a workaround for the waiting-related bug on Linux.
when saved or symlinked to as sublwait, provide a sublwait CLI that automatically applies the --wait and --new-window options so as to make it suitable for use with $EDITOR (note that some programs, e.g. npm, require the $EDITOR to contain the name of an executable only - executables + options are not supported); also makes sure that at least one file is specified.
The only open question is whether the OP's approach to avoiding the race condition - sleep 1 - is robust enough.
Update:
Note that subl on OSX is by default NOT placed in the $PATH - you normally have to do that manually. If you haven't done so, the script will now locate subl inside ST's application bundle; (it tries app names in the following sequence: 'Sublime Text', 'Sublime Text 2', 'Sublime Text 3', first in /Applications, then in ~/Applications.)
Here's the output from running the script with -h:
Multi-platform (OSX, Linux) wrapper script for invocation of Sublime Text (ST)
from the command line.
Linux:
Works around undesired blocking of the shell (unless requested)
and a bug when waiting for specific files to be edited.
Both platforms:
When invoked as `sublwait`, automatically applies the
--wait --new-window
options to make it suitable for use with $EDITOR.
Therefore, you can to the following:
- Name this script `subl` for a CLI that supports ALL options.
(On OSX, this will simply defer to the `subl` CLI that came with ST.)
- Place the script in a directory in your $PATH.
- In the same directory, create a symlink to the `subl` script named
`sublwait`:
ln -s subl sublwait
and, if desired, add
export EDITOR=sublwait
to your shell profile.
Note that if you only use OSX, you can make do with ST's own subl and just save this script directly as sublwait.
Script source:
#!/usr/bin/env bash
# Multi-platform (OSX, Linux) wrapper script for invocation of Sublime Text (ST)
# from the command line. Invoke with -h for details.
[[ $1 == '-h' || $1 == '--help' ]] && showHelpOnly=1 || showHelpOnly=0
[[ $(basename "$BASH_SOURCE") == 'sublwait' ]] && invokedAsSublWait=1 || invokedAsSublWait=0
[[ $(uname) == 'Darwin' ]] && isOsX=1 || isOsX=0
# Find the platform-appropriate ST executable.
if (( isOsX )); then # OSX: ST comes with a bona-fide CLI, `subl`.
# First, try to find the `subl` CLI in the $PATH.
# Note: This CLI is NOT there by default; it must be created by symlinking it from
# its location inside the ST app bundle.
# Find the `subl` executable, ignoring this script, if named subl' as well, or a
# script by that name in the same folder as this one (when invoked via symlink 'sublwait').
stExe=$(which -a subl | fgrep -v -x "$(dirname "$BASH_SOURCE")/subl" | head -1)
# If not already in the path, look for it inside the application bundle. Try several locations and versions.
if [[ -z $stExe ]]; then
for p in {,$HOME}"/Applications/Sublime Text"{,' 2',' 3'}".app/Contents/SharedSupport/bin/subl"; do
[[ -f $p ]] && { stExe=$p; break; }
done
fi
[[ -x $stExe ]] || { echo "ERROR: Sublime Text CLI 'subl' not found." 1>&2; exit 1; }
else # Linux: `sublime_text` is the only executable - the app itself.
stExe='sublime_text'
which "$stExe" >/dev/null || { echo "ERROR: Sublime Text executable '$stExe' not found." 1>&2; exit 1; }
fi
# Show command-line help, if requested.
# Add preamble before printing ST's own help.
# Note that we needn't worry about blocking the
# shell in this case - ST just outputs synchronously
# to stdout, then exits.
if (( showHelpOnly )); then
bugDescr=$(
cat <<EOF
works around a bug on Linux (as of v2.0.2), where Sublime Text,
if it is not already running, mistakenly blocks until it is exited altogether.
EOF
)
if (( invokedAsSublWait )); then
# We provide variant-specific help here.
cat <<EOF
Wrapper script for Sublime Text suitable for use with the \$EDITOR variable.
Opens the specified files for editing in a new window and blocks the
invoking program (shell) until they are closed.
In other words: the --wait and --new-window options are automatically
applied.
Aside from encapsulating this functionality without the need for options
- helpful for tools that require \$EDITOR to be an executable name only -
$bugDescr
Usage: sublwait file ...
EOF
# Note: Adding other options doesn't make sense in this scenario
# (as of v2.0.2), so we do NOT show ST's own help here.
else
cat <<EOF
Multi-platform (OSX, Linux) wrapper script for invocation of
Sublime Text (ST) from the command line.
Linux:
Works around undesired blocking of the shell (unless requested)
and a bug when waiting for specific files to be edited.
Both platforms:
When invoked as \`sublwait\`, automatically applies the
--wait --new-window
options to make it suitable for use with \$EDITOR.
Therefore, you can to the following:
- Name this script \`subl\` for a CLI that supports ALL options.
(On OSX, this will simply defer to the \`subl\` CLI that came with ST.)
- Place the script in a directory in your \$PATH.
- In the same directory, create a symlink to the \`subl\` script named
\`sublwait\`:
ln -s subl sublwait
and, if desired, add
export EDITOR=sublwait
to your shell profile.
Sublime Text's own help:
------------------------
EOF
# Finally, print ST's own help and exit.
exec "$stExe" "$#"
fi
exit 0
fi
# Invoked as `sublwait`? -> automatically apply --wait --new-window options.
if (( invokedAsSublWait )); then
# Validate parameters.
# - We expect NO options - to keep things simple and predictable, we do NOT allow
# specifying additional options (beyond the implied ones).
# - We need at least 1 file argument.
# - As a courtesy, we ensure that no *directories* are among the arguments - ST doesn't support
# that properly (always waits for ST exit altogether); beyond that, however, we leave input
# validation to ST.
if [[ "$1" =~ ^-[[:alnum:]]+$ || "$1" =~ ^--[[:alnum:]]+[[:alnum:]-]+$ ]]; then # options specified?
{ echo "ERROR: Unexpected option specified: '$1'. Use -h for help." 1>&2; exit 1; }
elif (( $# == 0 )); then # no file arguments?
{ echo "ERROR: Missing file argument. Use -h for help." 1>&2; exit 1; }
else # any directories among the arguments?
# Note: We do NOT check for file existence - files could be created on demand.
# (Things can still go wrong - e.g., /nosuchdir/mynewfile - and ST doesn't
# handle that gracefully, but we don't want to do too much here.)
for f in "$#"; do
[[ ! -d "$f" ]] || { echo "ERROR: Specifying directories is not supported: '$f'. Use -h for help." 1>&2; exit 1; }
done
fi
# Prepend the implied options.
set -- '--wait' '--new-window' "$#"
fi
# Finally, invoke ST:
if (( isOsX )); then # OSX
# `subl` on OSX handles all cases correctly; simply pass parameters through.
exec "$stExe" "$#"
else # LINUX: `sublime_text`, the app executable itself, does have a CLI, but it blocks the shell.
# Determine if the wait option was specified.
mustWait=0
if (( invokedAsSublWait )); then
mustWait=1
else
# Look for the wait option in the parameters to pass through.
for p in "$#"; do
[[ $p != -* ]] && break # past options
[[ $p == '--wait' || $p =~ ^-[[:alnum:]]*w[[:alnum:]]*$ ]] && { mustWait=1; break; }
done
fi
if (( mustWait )); then # Invoke in wait-for-specified-files-to-close mode.
# Quirk on Linux:
# If sublime_text isn't running yet, we must start it explicitly first.
# Otherwise, --wait will wait for ST *as a whole* to be closed before returning,
# which is undesired.
# Thanks, http://stackoverflow.com/questions/14598261/making-sublime-text-2-command-on-linux-behave-as-it-does-on-macos-x
if ! pidof "$stExe" 1>/dev/null; then
# Launch as BACKGROUND task to avoid blocking.
# (Sadly, the `--background` option - designed not to activate the Sublime Text window
# on launching - doesn't actually work on Linux (as of ST v2.0.2 on Ubuntu 12.04).)
("$stExe" --background &)
# !! We MUST give ST some time to start up, otherwise the 2nd invocation below will be ignored.
# ?? Does a fixed sleep time of 1 second work reliably?
sleep 1
fi
# Invoke in blocking manner, as requested.
exec "$stExe" "$#"
else # Ensure invocation in NON-blocking manner.
if ! pidof "$stExe" 1>/dev/null; then # ST isn't running.
# If ST isn't running, invoking it *always* blocks.
# Therefore, we launch it as a background taks.
# Invocation via a subshell (parentheses) suppresses display of the
# background-task 'housekeeping' info.
("$stExe" "$#" &)
else # ST is already running, we can safely invoke it directly without fear of blocking.
exec "$stExe" "$#"
fi
fi
fi
On Ubuntu Gnu/Linux 13.04 64-bit:
I just keep subl running pretty much all the time. So my git config has:
core.editor=/usr/bin/subl -n -w
And that's all I need. I save the git commit file with ctrl-s, close the window with ctrl-w and I'm done. But I then have to really close the window by hitting the X in the upper corner... 96% perfect.

Any way to exit bash script, but not quitting the terminal

When I use exit command in a shell script, the script will terminate the terminal (the prompt). Is there any way to terminate a script and then staying in the terminal?
My script run.sh is expected to execute by directly being sourced, or sourced from another script.
EDIT:
To be more specific, there are two scripts run2.sh as
...
. run.sh
echo "place A"
...
and run.sh as
...
exit
...
when I run it by . run2.sh, and if it hit exit codeline in run.sh, I want it to stop to the terminal and stay there. But using exit, the whole terminal gets closed.
PS: I have tried to use return, but echo codeline will still gets executed....
The "problem" really is that you're sourcing and not executing the script. When you source a file, its contents will be executed in the current shell, instead of spawning a subshell. So everything, including exit, will affect the current shell.
Instead of using exit, you will want to use return.
Yes; you can use return instead of exit. Its main purpose is to return from a shell function, but if you use it within a source-d script, it returns from that script.
As §4.1 "Bourne Shell Builtins" of the Bash Reference Manual puts it:
return [n]
Cause a shell function to exit with the return value n.
If n is not supplied, the return value is the exit status of the
last command executed in the function.
This may also be used to terminate execution of a script being executed
with the . (or source) builtin, returning either n or
the exit status of the last command executed within the script as the exit
status of the script.
Any command associated with the RETURN trap is executed
before execution resumes after the function or script.
The return status is non-zero if return is used outside a function
and not during the execution of a script by . or source.
You can add an extra exit command after the return statement/command so that it works for both, executing the script from the command line and sourcing from the terminal.
Example exit code in the script:
if [ $# -lt 2 ]; then
echo "Needs at least two arguments"
return 1 2>/dev/null
exit 1
fi
The line with the exit command will not be called when you source the script after the return command.
When you execute the script, return command gives an error. So, we suppress the error message by forwarding it to /dev/null.
Instead of running the script using . run2.sh, you can run it using sh run2.sh or bash run2.sh
A new sub-shell will be started, to run the script then, it will be closed at the end of the script leaving the other shell opened.
Actually, I think you might be confused by how you should run a script.
If you use sh to run a script, say, sh ./run2.sh, even if the embedded script ends with exit, your terminal window will still remain.
However if you use . or source, your terminal window will exit/close as well when subscript ends.
for more detail, please refer to What is the difference between using sh and source?
This is just like you put a run function inside your script run2.sh.
You use exit code inside run while source your run2.sh file in the bash tty.
If the give the run function its power to exit your script and give the run2.sh
its power to exit the terminator.
Then of cuz the run function has power to exit your teminator.
#! /bin/sh
# use . run2.sh
run()
{
echo "this is run"
#return 0
exit 0
}
echo "this is begin"
run
echo "this is end"
Anyway, I approve with Kaz it's a design problem.
I had the same problem and from the answers above and from what I understood what worked for me ultimately was:
Have a shebang line that invokes the intended script, for example,
#!/bin/bash uses bash to execute the script
I have scripts with both kinds of shebang's. Because of this, using sh or . was not reliable, as it lead to a mis-execution (like when the script bails out having run incompletely)
The answer therefore, was
Make sure the script has a shebang, so that there is no doubt about its intended handler.
chmod the .sh file so that it can be executed. (chmod +x file.sh)
Invoke it directly without any sh or .
(./myscript.sh)
Hope this helps someone with similar question or problem.
To write a script that is secure to be run as either a shell script or sourced as an rc file, the script can check and compare $0 and $BASH_SOURCE and determine if exit can be safely used.
Here is a short code snippet for that
[ "X$(basename $0)" = "X$(basename $BASH_SOURCE)" ] && \
echo "***** executing $name_src as a shell script *****" || \
echo "..... sourcing $name_src ....."
I think that this happens because you are running it on source mode
with the dot
. myscript.sh
You should run that in a subshell:
/full/path/to/script/myscript.sh
'source' http://ss64.com/bash/source.html
It's correct that sourced vs. executed scripts use return vs. exit to keep the same session open, as others have noted.
Here's a related tip, if you ever want a script that should keep the session open, regardless of whether or not it's sourced.
The following example can be run directly like foo.sh or sourced like . foo.sh/source foo.sh. Either way it will keep the session open after "exiting". The $# string is passed so that the function has access to the outer script's arguments.
#!/bin/sh
foo(){
read -p "Would you like to XYZ? (Y/N): " response;
[ $response != 'y' ] && return 1;
echo "XYZ complete (args $#).";
return 0;
echo "This line will never execute.";
}
foo "$#";
Terminal result:
$ foo.sh
$ Would you like to XYZ? (Y/N): n
$ . foo.sh
$ Would you like to XYZ? (Y/N): n
$ |
(terminal window stays open and accepts additional input)
This can be useful for quickly testing script changes in a single terminal while keeping a bunch of scrap code underneath the main exit/return while you work. It could also make code more portable in a sense (if you have tons of scripts that may or may not be called in different ways), though it's much less clunky to just use return and exit where appropriate.
Also make sure to return with expected return value. Else if you use exit when you will encounter an exit it will exit from your base shell since source does not create another process (instance).
Improved the answer of Tzunghsing, with more clear results and error re-direction, for silent usage:
#!/usr/bin/env bash
echo -e "Testing..."
if [ "X$(basename $0 2>/dev/null)" = "X$(basename $BASH_SOURCE)" ]; then
echo "***** You are Executing $0 in a sub-shell."
exit 0
else
echo "..... You are Sourcing $BASH_SOURCE in this terminal shell."
return 0
fi
echo "This should never be seen!"
Or if you want to put this into a silent function:
function sExit() {
# Safe Exit from script, not closing shell.
[ "X$(basename $0 2>/dev/null)" = "X$(basename $BASH_SOURCE)" ] && exit 0 || return 0
}
...
# ..it have to be called with an error check, like this:
sExit && return 0
echo "This should never be seen!"
Please note that:
if you have enabled errexit in your script (set -e) and you return N with N != 0, your entire script will exit instantly. To see all your shell settings, use, set -o.
when used in a function, the 1st return 0 is exiting the function, and the 2nd return 0 is exiting the script.
if your terminal emulator doesn't have -hold you can sanitize a sourced script and hold the terminal with:
#!/bin/sh
sed "s/exit/return/g" script >/tmp/script
. /tmp/script
read
otherwise you can use $TERM -hold -e script
If a command succeeded successfully, the return value will be 0. We can check its return value afterwards.
Is there a “goto” statement in bash?
Here is some dirty workaround using trap which jumps only backwards.
#!/bin/bash
set -eu
trap 'echo "E: failed with exitcode $?" 1>&2' ERR
my_function () {
if git rev-parse --is-inside-work-tree > /dev/null 2>&1; then
echo "this is run"
return 0
else
echo "fatal: not a git repository (or any of the parent directories): .git"
goto trap 2> /dev/null
fi
}
my_function
echo "Command succeeded" # If my_function failed this line is not printed
Related:
https://stackoverflow.com/a/19091823/2402577
How to use $? and test to check function?
I couldn't find solution so for those who want to leave the nested script without leaving terminal window:
# this is just script which goes to directory if path satisfies regex
wpr(){
leave=false
pwd=$(pwd)
if [[ "$pwd" =~ ddev.*web ]]; then
# echo "your in wordpress instalation"
wpDir=$(echo "$pwd" | grep -o '.*\/web')
cd $wpDir
return
fi
echo 'please be in wordpress directory'
# to leave from outside the scope
leave=true
return
}
wpt(){
# nested function which returns $leave variable
wpr
# interupts the script if $leave is true
if $leave; then
return;
fi
echo 'here is the rest of the script, executes if leave is not defined'
}
I have no idea whether this is useful for you or not, but in zsh, you can exit a script, but only to the prompt if there is one, by using parameter expansion on a variable that does not exist, as follows.
${missing_variable_ejector:?}
Though this does create an error message in your script, you can prevent it with something like the following.
{ ${missing_variable_ejector:?} } 2>/dev/null
1) exit 0 will come out of the script if it is successful.
2) exit 1 will come out of the script if it is a failure.
You can try these above two based on ur req.

Assign Unused Unicode Character in Ubuntu

I have a piece of old code that is trying to assign two unicode characters to one unused Unicode character (sorry, I am not using the right terms, but hopefully it gets the issue across). So U17ff is mapped to "ាំ" etc.
Here's the bash script:
for folder in /usr/X11R6/lib/X11/locale/*UTF-8
do
file="$folder/Compose"
if [ -f "$file" ] # is there a compose file?
then
if grep -q "<U17ff>" "$file" # is there Khmer in the file already
then
echo "Warning: $file includes Khmer already!"
else
cp --backup=t --force -v "$file" "$file" # create a backup file
cat Compose >>"$file" # append Khmer
echo "$file Khmer added"
fi
fi
done
The Compose file is this:
# Khmer digraphs
<U17ff> : "ាំ"
<U17fe> : "ោះ"
<U17fd> : "េះ"
<U17fc> : "ុំ"
<U17fb> : "ុះ"
I think the directory isn't right for this code, so the keyboard it is trying to install doesn't work because the unicode character it calls is still blank (I've used the default Khmer keyboard that comes with Ubuntu, and it doesn't work properly, so I am trying to fix it).
Can anyone tell me the directory I should use rather than /usr/X11R6/lib/X11/locale/*UTF-8
For Ubuntu 11.x?
Thanks,
Nathan
Turns out this was a bigger issue than I thought (it is a bug), but there is a way around it:
Type
sudo gedit /etc/environment
Add a line
GTK_IM_MODULE=xim
Save and close.
4.Then in terminal type:
sudo gedit /usr/share/X11/locale/en_US.UTF-8/Compose
Gedit should open, search for Khmer and make sure the following exists (if not, copy and paste it in):
#
# Khmer digraphs
#
<U17ff> : "ាំ"
<U17fe> : "ោះ"
<U17fd> : "េះ"
<U17fc> : "ុំ"
<U17fb> : "ុះ"
Save and reboot.
And everything works fine.

Resources