Positional Parameters Arguments/Variables when using dot (.)

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# 1  
Positional Parameters Arguments/Variables when using dot (.)


Is there a special positional variables for when using the dot (.)?

Scripts are as below:

$: head -100 x.ksh /tmp/y.ksh
==> x.ksh <==
. /tmp/y.ksh 1234 abcd

echo "yvar1 = $yvar1"
echo "yvar2 = $yvar2"

==> /tmp/y.ksh <==

echo "======================================"
echo "\$* = $*"
echo "\$@ = $@"
echo "======================================"
echo "\$0 = $0"
echo "\$1 = $1"
echo "\$2 = $2"

#export yvar1="YVAR_1"
#export yvar2="YVAR_2"


Sample run below:

$: ./x.ksh


$* = 1234 abcd
$@ = 1234 abcd


$0 = ./x.ksh
$1 = 1234
$2 = abcd

yvar1 = YVAR_1
yvar2 = YVAR_2

I am expecting /tmp/y.ksh to print in $0 or $1 but it isn't. Is there a special variable for when calling another script using the dot (.)?
# 2  
I am at a loss as to what you are trying to do.
IF you are sourcing a file, . /path/to/file then that will execute inside the parent shell.
Variables will be passed at that position where the sourced file is...
A quick demo...
Sourced file:
# Test file to be sourced.


echo "Inside source file \${MYVAR} = ${MYVAR}"

AND parent file:
# Parent test file...

# Sourced file in the same directory.
. ./source_file.sh 'UNIX'

echo "Sourced file \${MYVAR} = ${MYVAR}"


echo "Parent file \${MYVAR} = ${MYVAR}"

. ./source_file.sh 'LINUX'

echo "Sourced file \${MYVAR} = ${MYVAR}"

Results OSX 10.14.6, default shell terminal.
Last login: Wed Oct  9 14:38:32 on ttys000
AMIGA:amiga~> cd Desktop/Code/Shell
AMIGA:amiga~/Desktop/Code/Shell> chmod 755 parent_file.sh
AMIGA:amiga~/Desktop/Code/Shell> chmod 755 source_file.sh
AMIGA:amiga~/Desktop/Code/Shell> ./parent_file.sh
Inside source file ${MYVAR} = UNIX
Sourced file ${MYVAR} = UNIX
Parent file ${MYVAR} = Bazza
Inside source file ${MYVAR} = LINUX
Sourced file ${MYVAR} = LINUX
AMIGA:amiga~/Desktop/Code/Shell> _

# 3  
There's not a standard, "compatible" way, but there's often a way to get it:

$ cat dot1.sh

# dot1.sh

echo "$0 1=$1 2=$2 file=$file"

set | grep dot1

. ./dot2.sh a b

$ cat dot2.sh

echo "$0 1=$1 2=$2"

set | grep "dot2"

$ ./dot1.sh 1 2

./dot1.sh 1=1 2=2 file=
_='./dot1.sh 1=1 2=2 file='
./dot1.sh 1=a 2=b
BASH_SOURCE=([0]="./dot2.sh" [1]="./dot1.sh")

$ sed -i 's/bash/ksh/' dot1.sh # replace bash with ksh

./dot1.sh 1=1 2=2 file=
_='./dot1.sh 1=1 2=2 file='
./dot1.sh 1=a 2=b


This 'file' isn't a real variable, unfortunately, just something to be snagged from set. I think BASH_SOURCE is a real array however.
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