libbb: make read_cmdline() replace chars 1..31 with '?', not space

Space was too inconspicuous on output

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/libbb/procps.c b/libbb/procps.c
index fc31c075d..94bbd9eb5 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -578,7 +578,7 @@ int FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
                  */
                 while (sz >= 0) {
                         if ((unsigned char)(buf[sz]) < ' ')
-                                buf[sz] = ' ';
+                                buf[sz] = (buf[sz] ? /*ctrl*/'?' : /*NUL*/' ');
                         sz--;
                 }