avoid executing unsafe functions if we get a terminating signal while handling SIGCHLD; reject attempts to modify some attributes for readonly variables; more changes for unlocked stdio functions; quoting fixes for uncommon cases where IFS = ^A and the word is not being split

tests/array.right

@@ -70,7 +70,7 @@ declare -a d=([1]="test test")
 declare -a e=()
 declare -a f=([0]="" [1]="bdef" [2]="hello world" [3]="test" [4]="ninth element")
 ./array.tests: line 137: unset: ps1: not an array variable
-./array.tests: line 141: declare: c: cannot destroy array variables in this way
+./array.tests: line 141: declare: c: readonly variable
 this of
 this is a test of read using arrays
 this test

tests/attr.right

@@ -1,5 +1,5 @@
 after f1:declare -ar a=([0]="1")
-./attr.tests: line 17: a: readonly variable
+./attr.tests: line 17: f2: a: readonly variable
 after f2:declare -ar a=([0]="1")
 ./attr.tests: line 18: a: readonly variable
 after f3:declare -ar a=([0]="1")
@@ -17,7 +17,7 @@ declare -r p="1"
 declare -ar r=([0]="1")
 ./attr1.sub: line 36: r: readonly variable
 declare -ar r=([0]="1")
-./attr1.sub: line 40: r: readonly variable
+./attr1.sub: line 40: f: r: readonly variable
 declare -ar r=([0]="1")
 ./attr1.sub: line 44: readonly: r: readonly variable
 declare -ar r=([0]="1")

tests/dollar-at-star

@@ -329,4 +329,7 @@ ${THIS_SH} ./dollar-star9.sub
 # null strings as the positional parameters
 ${THIS_SH} ./dollar-star10.sub
 
+# tests for expansions of $* when IFS=$'\1'
+${THIS_SH} ./dollar-star11.sub
+
 exit 0

tests/dollar-star11.sub

@@ -0,0 +1,43 @@
+set aa bb cc -- dd ; f=$'\1' IFS=$f
+
+recho "$f$*$f"
+recho "$f--$f"
+
+[[ $f$*$f == *$f--$f* ]] && echo ok 1
+[[ $f$*$f == "$f--$f" ]] || echo ok 2
+
+[[ ${f}${*}${f} == *$f--$f* ]] && echo ok 3
+
+[[ $f$*$f == $f$*$f ]] && echo ok 4
+[[ ${f}${*}${f} == $f$*$f ]] && echo ok 5
+[[ $f$*$f == *--* ]] && echo ok 6
+
+[[ $* == $* ]] && echo ok 7
+[[ $* == ${*} ]] && echo ok 8
+[[ $f == $f ]] && echo ok 9
+[[ $f == ${f} ]] && echo ok 10
+
+# now with f an array and $f -> ${f[0]}
+
+set aa bb cc -- dd ; f=( $'\1' )
+
+[[ $f$*$f == *$f--$f* ]] && echo ok 11
+[[ ${f}${*}${f} == *$f--$f* ]] && echo ok 12
+[[ $f$*$f == $f$*$f ]] && echo ok 13
+[[ ${f}${*}${f} == $f$*$f ]] && echo ok 14
+[[ $f$*$f == *--* ]] && echo ok 15
+
+[[ $* == $* ]] && echo ok 16
+[[ $* == ${*} ]] && echo ok 17
+[[ $f == $f ]] && echo ok 18
+[[ $f == ${f} ]] && echo ok 19
+
+# now use an array instead of $*
+A=( aa bb cc -- dd ); f=$'\1' IFS=$f
+
+[[ $f${A[*]}$f == $f${A[*]}$f ]] && echo ok 20
+[[ $f${A[*]}$f == *--* ]] && echo ok 21
+[[ ${f}${A[*]}${f} == *$f--$f* ]] && echo ok 22
+
+[[ ${f}${A[*]}${f} == $f${A[*]}$f ]] && echo ok 23
+[[ ${A[*]} == ${A[*]} ]] && echo ok 24

tests/dollar.right

@@ -742,3 +742,29 @@ argv[2] = <2>
 var=1 2
 argv[1] = <1 2>
 argv[1] = <1 2>
+argv[1] = <^Aaa^Abb^Acc^A--^Add^A>
+argv[1] = <^A--^A>
+ok 1
+ok 2
+ok 3
+ok 4
+ok 5
+ok 6
+ok 7
+ok 8
+ok 9
+ok 10
+ok 11
+ok 12
+ok 13
+ok 14
+ok 15
+ok 16
+ok 17
+ok 18
+ok 19
+ok 20
+ok 21
+ok 22
+ok 23
+ok 24