"parse error near `|'" when sourcing script file in zsh - zsh

I'm using zsh (5.4.2) with oh-my-zsh as my shell on Ubuntu 18.04.
The following script is executed correctly in zsh when I just run it (./my_script -a 1):
#! /bin/bash
while getopts "a:" OPTION; do
case $OPTION in
a)
[[ ! $OPTARG =~ 1|2|3 ]] && {
echo "Incorrect architecture provided"
}
esac
done
echo "End"
But when I'm sourcing it (source ./my_script.sh -a 1) zsh prints the following error: parse error near '|'.
What could be the possible reason?
Here is my .zshrc:
# Path to your oh-my-zsh installation.
export ZSH="/home/ievgen.popovych/.oh-my-zsh"
ZSH_THEME="agnoster"
COMPLETION_WAITING_DOTS="true"
plugins=(git colored-man-pages colorize command-not-found copydir copyfile cp dircycle dirpersist safe-paste tmux themes)
source $ZSH/oh-my-zsh.sh
export EDITOR='nvim'
# Setup dircolors
theme=ansi-light
eval `dircolors -b ~/dircolors-solarized/dircolors.$theme`
alias zshconfig="nvim ~/.zshrc"
alias gitconfig="nvim ~/.gitconfig"
alias nvconfig="nvim ~/.config/nvim/init.vim"
alias nvbundle="cd ~/.config/nvim/bundle && git clone "
alias nv="nvim"
alias debinstall="sudo dpkg -i "
alias zshr="source ~/.zshrc"
alias tmuxconfig="nvim ~/.tmux.conf"
alias cdbundle="cd ~/.config/nvim/bundle"
# git aliases
alias gs="git s"
alias gb="git b"
alias gco="git co"
alias gl="git l"
alias gp="git push"
alias gcreate="git create"
alias gamend="git amend"
alias gaa="git aa"
alias gfixup="git fixup"
alias gsquash="git squash"
alias gsymref="git symref"

When you execute the script using ./my_script -a 1, you aren't using zsh; you are using bash.
You can either escape the |
[[ ! $OPTARG =~ 1\|2\|3 ]]
[[ ! $OPTARG =~ "1|2|3" ]]
or store the regular expression in a variable
regex="1|2|3"
[[ ! $OPTARG =~ $regex ]]
The latter is necessary if you want the same code to work in both bash and zsh, but as a general rule writing code that works identically in both shells is more trouble than it is worth, assuming it is possible.

Assuming that you really run your script under zsh, you have to use parenthesis when using alternatives in a regexp:
[[ ! $OPTARG =~ (1|2|3) ]]

Related

Unexpected no such file error in zsh function

I have defined this function in zsh, but it cannot work on my computer.
function m() {
local path=/Users/james/Music/cloud_music_link
local cmd="ls $path | sed -n $1p"
echo `$cmd`
# afplay `$cmd`
}
It always said:
m:3: no such file or directory: ls /Users/james/Music/cloud_music_link | sed -n 10p
and when I copy the ls /Users/james/Music/cloud_music_link | sed -n 10p and run it in zsh, everything is ok, why would this happen?
And the folder cloud_music_link is a soft link, I am not sure if this matters.
You want to pass the file (or subdirectory) at a given position inside of your given directory first to echo, and then to aplay? Easily done, in a way compatible with both bash and zsh:
m() {
local num=${1:-1}
local dir=/Users/james/Music/cloud_music_link
local -a files=( "$dir"/* )
local file=${files[$(( num - 1 ))]}
echo "$file"
afplay "$file" &
}
See:
Why you shouldn't parse the output of ls
I'm trying to put a command in a variable, but complex cases always fail!
Finally I have figured it out, it is because the name of the variable path, I changed it to p and everything works OK. The name path will conflict with zsh.
This code works:
function m() {
local p=/Users/james/Music/cloud_music_link/
song="$(ls $p | sed -n $1p)"
echo $song
killall afplay
afplay "$p$song"&
}

Run arbitrary zsh command for all subfolders

I'm currently using this function to run a command for all subfolders in zsh.
forsubdirs() {
for dir in *; do
(cd ${dir} && echo $fg_bold[yellow]${PWD##*/}$reset_color && $# && echo '\n')
done
}
I use it like this: forsubdirs git pull
The problem, though: it does not work with aliases. How to execute an arbitrary ZSH command (including aliases and lists of commands separated with "&" or ";") for all subfolders?
In order to be able to pass complex commands as argument you need to quote syntactic elements like ; and &. The arguments then need to be explicitly evaluated with the eval command. For example:
forsubdirs () {
for dir in *(/) ; do
( cd $dir && echo $fg_bold[yellow]${PWD##*/}$reset_color && eval $# && echo '\n' )
done
}
forsubdir 'ls -1 | sed "s/^/ /"'
Also, I would suggest using *(/) instead of plain *. It matches only directories, so that the function does not even try to run cd on regular files.

substring before and substring after in shell script

I have a string:
//host:/dir1/dir2/dir3/file_name
I want to fetch value of host & directories in different variables in unix script.
Example :
host_name = host
dir_path = /dir1/dir2/dir3
Note - String length & no of directories is not fixed.
Could you please help me to fetch these values from string in unix shell script.
Using bash string operations:
str='//host:/dir1/dir2/dir3/file_name'
host_name=${str%%:*}
host_name=${host_name##*/}
dir_path=${str#*:}
dir_path=${dir_path%/*}
I would do it using regular expressions:
if [[ $path =~ ^//(.*):(.*)/(.*)$ ]]; then
host="${BASH_REMATCH[1]}"
dir_path="${BASH_REMATCH[2]}"
filename="${BASH_REMATCH[3]}"
else
echo "Invalid format" >&2
exit 1
fi
If you are sure that the format will match, you can do simply
[[ $path =~ ^//(.*):(.*)/(.*)$ ]]
host="${BASH_REMATCH[1]}"
dir_path="${BASH_REMATCH[2]}"
filename="${BASH_REMATCH[3]}"
Edit: Since you seem to be using ksh rather than bash (though bash was indicated in the question), the syntax is a bit different:
match=(${path/~(E)^\/\/(.*):(.*)\/(.*)$/\1 \2 \3})
host="${match[0]}"
dir_path="${match[1]}"
filename="${match[2]}"
This will break if there are spaces in the file name, though. In that case, you can use the more cumbersome
host="${path/~(E)^\/\/(.*):(.*)\/(.*)$/\1}"
dir_path="${path/~(E)^\/\/(.*):(.*)\/(.*)$/\2}"
filename="${path/~(E)^\/\/(.*):(.*)\/(.*)$/\3}"
Perhaps there are more elegant ways of doing it in ksh, but I'm not familiar with it.
The shortest way I can think of is to assign two variables in one statement:
$ read host_name dir_path <<< $(echo $string | sed -e 's,^//,,;s,:, ,')
Complete script:
string="//host:/dir1/dir2/dir3/file_name"
read host_name dir_path <<< $(echo $string | sed -e 's,^//,,;s,:, ,')
echo "host_name = " $host_name
echo "dir_path = " $dir_path
Output:
host_name: host
dir_path: /dir1/dir2/dir3/file_name

How to custom display prompt in KornShell to show hostname and current directory?

I am using KornShell (ksh) on Solaris and currently my PS1 env var is:
PS1="${HOSTNAME}:\${PWD} \$ "
And the prompt displays: hostname:/full/path/to/current/directory $
However, I would like it to display: hostname:directory $
In other words, how can I display just the hostname and the name of the current directory, i.e. tmp or ~ or public_html etc etc?
From reading the ksh man page you want
PS1="${HOSTNAME}:\${PWD##*/} \$ "
Tested on default ksh on SunOS 5.8
Okay, a little old and a little late, but this is what I use in Kornshell:
PS1='$(print -n "`logname`#`hostname`:";if [[ "${PWD#$HOME}" != "$PWD" ]] then; print -n "~${PWD#$HOME}"; else; print -n "$PWD";fi;print "\n$ ")'
This makes a prompt that's equivalent to PS1="\u#\h:\w\n$ " in BASH.
For example:
qazwart#mybook:~
$ cd bin
qazwart#mybook:~/bin
$ cd /usr/local/bin
qazwart#mybook:/usr/local/bin
$
I like a two line prompt because I sometimes have very long directory names, and they can take up a lot of the command line. If you want a one line prompt, just leave off the "\n" on the last print statement:
PS1='$(print -n "`logname`#`hostname`:";if [[ "${PWD#$HOME}" != "$PWD" ]] then; print -n "~${PWD#$HOME}"; else; print -n "$PWD";fi;print "$ ")'
That's equivalent to PS1="\u#\h:\w$ " in BASH:
qazwart#mybook:~$ cd bin
qazwart#mybook:~/bin$ cd /usr/local/bin
qazwart#mybook:/usr/local/bin$
It's not quite as easy as setting up a BASH prompt, but you get the idea. Simply write a script for PS1 and Kornshell will execute it.
For Solaris and other Older Versions of Kornshell
I found that the above does not work on Solaris. Instead, you'll have to do it the real hackish way...
In your .profile, make sure that ENV="$HOME/.kshrc"; export ENV
is set. This is probably setup correctly for you.
In your .kshrc file, you'll be doing two things
You'll be defining a function called _cd. This function will change to the directory specified, and then set your PS1 variable based upon your pwd.
You'll be setting up an alias cd to run the _cd function.
This is the relevant part of the .kshrc file:
function _cd {
logname=$(logname) #Or however you can set the login name
machine=$(hostname) #Or however you set your host name
$directory = $1
$pattern = $2 #For "cd foo bar"
#
# First cd to the directory
# We can use "\cd" to evoke the non-alias original version of the cd command
#
if [ "$pattern" ]
then
\cd "$directory" "$pattern"
elif [ "$directory" ]
then
\cd "$directory"
else
\cd
fi
#
# Now that we're in the directory, let's set our prompt
#
$directory=$PWD
shortname=${directory#$HOME} #Possible Subdir of $HOME
if [ "$shortName" = "" ] #This is the HOME directory
then
prompt="~$logname" # Or maybe just "~". Your choice
elif [ "$shortName" = "$directory" ] #Not a subdir of $HOME
then
prompt="$directory"
else
prompt="~$shortName"
fi
PS1="$logname#$hostname:$prompt$ " #You put it together the way you like
}
alias cd="_cd"
This will set your prompt as the equivelent BASH PS1="\u#\h:\w$ ". It isn't pretty, but it works.
ENV=~/.kshrc, and then in your .kshrc:
function _cd {
\cd "$#"
PS1=$(
print -n "$LOGNAME#$HOSTNAME:"
if [[ "${PWD#$HOME}" != "$PWD" ]]; then
print -n "~${PWD#$HOME}"
else
print -n "$PWD"
fi
print "$ "
)
}
alias cd=_cd
cd "$PWD"
Brad
HOST=`hostname`
PS1='$(print -n "[${USER}#${HOST%%.*} ";[[ "$HOME" == "$PWD" ]] && print -n "~" ||([[ "${PWD##*/}" == "" ]] && print -n "/" || print -n "${PWD##*/}");print "]$")'
PS1=`id -un`#`hostname -s`:'$PWD'$
and...
if you work between two shells for most of your effort [ksh and bourne sh]
and desire a directory tracking display on your command line
then PWD can be substituted easily in ksh
and if you use /usr/xpg4/bin/sh for your sh SHELL, it will work there as well
Try this:
PS1="\H:\W"
More information on: How to: Change / Setup bash custom prompt, I know you said ksh, but I am pretty sure it will work.

Find out if a command exists on POSIX system

I want to be able to tell if a command exists on any POSIX system from a shell script.
On Linux, I can do the following:
if which <command>; then
...snip...
fi
However, Solaris and MacOS which do not give an exit failure code when the command does not exist, they just print an error message to STDOUT.
Also, I recently discovered that the which command itself is not POSIX (see http://pubs.opengroup.org/onlinepubs/9699919799/idx/utilities.html)
Any ideas?
command -v is a POSIX specified command that does what which does.
It is defined to to return >0 when the command is not found or an error occurs.
You could read the stdout/stderr of "which" into a variable or an array (using backticks) rather than checking for an exit code.
If the system does not have a "which" or "where" command, you could also grab the contents of the $PATH variable, then loop over all the directories and search for the given executable. That's essentially what which does (although it might use some caching/optimization of $PATH results).
One which utility is available as shell script in the Git repository of debianutils package of Debian Linux. The script seems to be POSIX compatible and you could use it, if you take into account copyright and license. Note that there have been some controversy whether or not and how the which utility should be deprecated; (at time of writing) current version in Git shows deprecation message whereas an earlier version added later removed -s option to enable silent operation.
command -v as such is problematic as it may output a shell function name, an alias definition, a keyword, a builtin or a non-executable file path. On the other hand some path(s) output by which would not be executed by shell if you run the respective argument as such or as an argument for command. As an alternative for using the which script, a POSIX shell function using command -v could be something like
#!/bin/sh
# Argument $1 should be the basename of the command to be searched for.
# Outputs the absolute path of the command with that name found first in
# a directory listed in PATH environment variable, if the name is not
# shadowed by a special built-in utility, a regular built-in utility not
# associated with a PATH search, or a shell reserved word; otherwise
# outputs nothing and returns 1. If this function prints something for
# an argument, it is the path of the same executable as what 'command'
# would execute for the same argument.
executable() {
if cmd=$(unset -f -- "$1"; command -v -- "$1") \
&& [ -z "${cmd##/*}" ] && [ -x "$cmd" ]; then
printf '%s\n' "$cmd"
else
return 1
fi
}
Disclaimer: Note that the script using command -v above does not find an executable whose name equals a name of a special built-in utility, a regular built-in utility not associated with a PATH search, or a shell reserved word. It might not find an executable either in case if there is non-executable file and executable file available in PATH search.
A function_command_exists for checking if a command exists:
#!/bin/sh
set -eu
function_command_exists() {
local command="$1"
local IFS=":" # paths are delimited with a colon in $PATH
# iterate over dir paths having executables
for search_dir in $PATH
do
# seek only in dir (excluding subdirs) for a file with an exact (case sensitive) name
found_path="$(find "$search_dir" -maxdepth 1 -name "$command" -type f 2>/dev/null)"
# (positive) if a path to a command was found and it was executable
test -n "$found_path" && \
test -x "$found_path" && \
return 0
done
# (negative) if a path to an executable of a command was not found
return 1
}
# example usage
echo "example 1";
command="ls"
if function_command_exists "$command"; then
echo "Command: "\'$command\'" exists"
else
echo "Command: "\'$command\'" does not exist"
fi
command="notpresent"
if function_command_exists "$command"; then
echo "Command: "\'$command\'" exists"
else
echo "Command: "\'$command\'" does not exist"
fi
echo "example 2";
command="ls"
function_command_exists "$command" && echo "Command: "\'$command\'" exists"
command="notpresent"
function_command_exists "$command" && echo "Command: "\'$command\'" does not exist"
echo "End of the script"
output:
example 1
Command: 'ls' exists
Command: 'notpresent' does not exist
example 2
Command: 'ls' exists
End of the script
Note that even the set -eu that turns -e option for the script was used the script was executed to the last line "End of the script"
There is no Command: 'notpresent' does not exist in the example 2 because of the && operator so the execution of echo "Command: "\'$command\'" does not exist" is skipped but the execution of the script continues till the end.
Note that the function_command_exists does not check if you have a right to execute the command. This needs to be done separately.
Solution with command -v <command-to-check>
#!/bin/sh
set -eu;
# check if a command exists (Yes)
command -v echo > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 1>"
fi
# check if a command exists (No)
command -v command-that-does-not-exists > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 2>"
fi
produces:
<handle not found 2>
because echo was found at the first example.
Solution with running a command and handling errors including command not found.
#!/bin/sh
set -eu;
# check if a command exists (No)
command -v command-that-does-not-exist > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 2>"
fi
# run command and handle errors (no problem expected, echo exist)
echo "three" && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 3>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 3>"
fi
# run command and handle errors (<handle not found 4> expected)
command-that-does-not-exist && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 4>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 4>"
fi
# run command and handle errors (command exists but <handle other error 5> expected)
ls non-existing-path && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 5>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 5>"
fi
produces:
<handle not found 2>
three
./function_command_exists.sh: 34: ./function_command_exists.sh: command-that-does-not-exist: not found
<handle not found 4>
ls: cannot access 'non-existing-path': No such file or directory
<handle other error 5>
The following works in both bash and zsh and avoids both functions and aliases.
It returns 1 if the binary is not found.
bin_path () {
if [[ -n ${ZSH_VERSION:-} ]]; then
builtin whence -cp "$1" 2> /dev/null
else
builtin type -P "$1"
fi
}

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