On 2026-03-11 08:49, Pádraig Brady wrote:
+(
+ ulimit -S -f 1024 || skip_ 'unable to set file size ulimit'
+ trap '' XFSZ || skip_ 'unable to ignore SIGXFSZ'
+ dd if=/dev/zero of=f bs=768K count=2 2>err
+ echo $? > dd.ret
+)
+
+if test "$(cat dd.ret)" = 1; then
+ grep -F '+1 records out' err || { cat err; fail=1; }
+fi
Not clear why we have to put the exit status into dd.ret; can't we just
inspect $? after the (...) finishes?
There's a problem with doing a ulimit -f in a test script: it also
limits the size of the test trace output by the shell. Although 768K
should be safe, better to place the limit where it actually should be,
for safety in a subsidiary shell invocation. Something like this, perhaps?
cat <<\EOF > experr-XFSZ || framework_failure_
dd: error writing 'out-XFSZ': File too large
2+0 records in
1+1 records out
EOF
dd ibs=2048 obs=2048 count=1 if=/dev/zero of=exp-XFSZ &&
! $SHELL -c '
ulimit -S -f 4 && trap "" XFSZ && \
exec dd bs=1536 status=noxfer if=/dev/zero of=out-XFSZ 2>err-XFSZ
' &&
compare exp-XFSZ out-XFSZ &&
compare experr-XFSZ err-XFSZ || fail=1
