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|
#
# varenv.sh
#
# Test the behavior of the shell with respect to variable and environment
# assignments
#
expect()
{
echo expect "$@"
}
a=1
b=2
c=3
d=4
e=5
f=6 g=7 h=8
a=3 b=4 $CHMOD $MODE $FN
# This should echo "3 4" according to Posix.2
expect "3 4"
echo $a $b
set -k
# Assignment statements made when no words are left affect the shell's
# environment
a=5 b=6 $CHMOD c=7 $MODE d=8 $FN e=9
expect "5 6 7 8 9"
echo $a $b $c $d $e
$CHMOD f=7 $MODE g=8 $FN h=9
expect "7 8 9"
echo $f $g $h
set +k
# The temporary environment does not affect variable expansion, only the
# environment given to the command
export HOME=/usr/chet
expect $HOME
echo $HOME
expect $HOME
HOME=/a/b/c /bin/echo $HOME
expect $HOME
echo $HOME
# This should echo /a/b/c
expect /a/b/c
HOME=/a/b/c printenv HOME
set -k
# This should echo $HOME 9, NOT /a/b/c 9
expect "$HOME"
HOME=/a/b/c /bin/echo $HOME c=9
expect "$HOME 7"
echo $HOME $c
# I claim the next two echo calls should give identical output.
# ksh agrees, the System V.3 sh does not
expect "/a/b/c 9 /a/b/c"
HOME=/a/b/c $ECHO a=$HOME c=9
echo $HOME $c $a
expect "/a/b/c 9 /a/b/c"
HOME=/a/b/c a=$HOME c=9
echo $HOME $c $a
set +k
# How do assignment statements affect subsequent assignments on the same
# line?
expect "/a/b/c /a/b/c"
HOME=/a/b/c a=$HOME
echo $HOME $a
# The system V.3 sh does this wrong; the last echo should output "1 1",
# but the system V.3 sh has it output "2 2". Posix.2 says the assignment
# statements are processed left-to-right. bash and ksh output the right
# thing
c=1
d=2
expect "1 2"
echo $c $d
d=$c c=$d
expect "1 1"
echo $c $d
# just for completeness
unset d c
expect unset
echo ${d-unset}
# no output
export a
a=bcde
export a
/bin/true 2>/dev/null
func()
{
local YYZ
YYZ="song by rush"
echo $YYZ
echo $A
}
YYZ="toronto airport"
A="AVAR"
echo $YYZ
echo $A
A=BVAR func
echo $YYZ
echo $A
export A
# Make sure expansion doesn't use assignment statements preceding a builtin
A=ZVAR echo $A
PATH=/bin:/usr/bin:/usr/local/bin:.
func2()
{
local z=yy
local -a avar=( ${PATH//: } )
echo ${avar[@]}
local
}
avar=42
echo $avar
func2
echo $avar
# try to set an attribute for an unset variable; make sure it persists
# when the variable is assigned a value
declare -i ivar
ivar=10
declare -p ivar
unset ivar
# export an unset variable, make sure it is not suddenly set, but make
# sure the export attribute persists when the variable is assigned a
# value
export ivar
echo ${ivar-unset}
ivar=42
declare -p ivar
# make sure set [-+]o ignoreeof and $IGNOREEOF are reflected
unset IGNOREEOF
set +o ignoreeof
set -o ignoreeof
if [ "$IGNOREEOF" -ne 10 ]; then
echo "./varenv.sh: set -o ignoreeof is not reflected in IGNOREEOF" >&2
fi
unset IGNOREEOF
set +o ignoreeof
# older versions of bash used to not reset RANDOM in subshells correctly
[[ $RANDOM -eq $(echo $RANDOM) ]] && echo "RANDOM: problem with subshells"
# make sure that shopt -o is reflected in $SHELLOPTS
# first, get rid of things that might be set automatically via shell
# variables
set +o posix
set +o ignoreeof
set +o monitor
echo $-
echo ${SHELLOPTS}
shopt -so physical
echo $-
echo ${SHELLOPTS}
# and make sure it is readonly
readonly -p | grep SHELLOPTS
|
