[BUG]? Strange return values of close()

[Jakub Martisko]

Hello,

there seems to be some strange behaviour with the close (reproducer is
attached in case the formatting gets messed). Is the RC echo=2304 expected
or is this a bug? I've tested the same thing with the gawk-4.0.2 (i.e.
before the change described in) and it returns 2304 in all four cases.

Thanks,
Jakub

[1]:
https://www.gnu.org/software/gawk/manual/html_node/Close-Files-And-Pipes.html#FOOT29

$ ls
gwk_prog
$ gawk -f ./gwk_prog
RC Empty=9 #this is the expected value based on unzip's return values
RC echo=9
$ unzip -o ./test.zip 2>/dev/null; echo $?
9

$ touch ./test.zip

$ ls

gwk_prog  test.zip
$ gawk -f ./gwk_prog
RC Empty=9
RC echo=2304 # this is 256*9 btw
$ unzip -o ./test.zip 2>/dev/null; echo $?

Archive:  ./test.zip
9

$ cat gwk_prog
#!/usr/bin/gawk -f

BEGIN{
rc=0;

extract_file="unzip -o ./test.zip 2>/dev/null";

#Just an empty cycle - returns 9 as expected
while (extract_file|getline){
continue;
}
rc=close(extract_file);
print "RC Empty="rc;


#Non empty cycle - extract_file should return 9
while (extract_file|getline){
cmd="echo"
cmd|getline
close(cmd)
}
rc=close(extract_file);
print "RC echo="rc;
}

gwk_prog
Description: Binary data