xread/xwrite: clip MAX_IO_SIZE to SSIZE_MAX

diff --git a/t/t5100-mailinfo.sh b/t/t5100-mailinfo.sh
index 81904d9ec8d341399b534c5d576262439d0e1ad6..3e64a7a65da86410dd0236975bef9bd0013a6405 100755 (executable)
--- a/t/t5100-mailinfo.sh
+++ b/t/t5100-mailinfo.sh
@@ -11,7 +11,7 @@ test_expect_success 'split sample box' \
        'git mailsplit -o. "$TEST_DIRECTORY"/t5100/sample.mbox >last &&
        last=`cat last` &&
        echo total is $last &&
-       test `cat last` = 16'
+       test `cat last` = 17'
 
 check_mailinfo () {
        mail=$1 opt=$2