testcommon: spawn-aware system() and qx[] workalikes

Barely noticeable on Linux, but this gives a 1-2% speedup
on a FreeBSD 11.3 VM and lets us use built-in redirects
rather than relying on /bin/sh.

1 files changed, 3 insertions, 3 deletions

diff --git a/xt/git-http-backend.t b/xt/git-http-backend.t
index f2ae44fe..2f02725a 100644
--- a/xt/git-http-backend.t
+++ b/xt/git-http-backend.t
@@ -83,13 +83,13 @@ SKIP: { # make sure Last-Modified + If-Modified-Since works with curl
         skip 'curl(1) not found', $nr unless $curl;
         my $url = "http://$host:$port/description";
         my $dst = "$tmpdir/desc";
-        is(system($curl, qw(-RsSf), '-o', $dst, $url), 0, 'curl -R');
+        is(xsys($curl, qw(-RsSf), '-o', $dst, $url), 0, 'curl -R');
         is((stat($dst))[9], $mtime, 'curl used remote mtime');
-        is(system($curl, qw(-sSf), '-z', $dst, '-o', "$dst.2", $url), 0,
+        is(xsys($curl, qw(-sSf), '-z', $dst, '-o', "$dst.2", $url), 0,
                 'curl -z noop');
         ok(!-e "$dst.2", 'no modification, nothing retrieved');
         utime(0, 0, $dst) or die "utime failed: $!";
-        is(system($curl, qw(-sSfR), '-z', $dst, '-o', "$dst.2", $url), 0,
+        is(xsys($curl, qw(-sSfR), '-z', $dst, '-o', "$dst.2", $url), 0,
                 'curl -z updates');
         ok(-e "$dst.2", 'faked modification, got new file retrieved');
 }