chat: new applet by dronnikov AT gmail.com. With all options on:

function                                             old     new   delta
chat_main                                              -    1230   +1230
unescape                                               -     135    +135
packed_usage                                       23802   23922    +120
signal_handler                                       123     131      +8
input_backward                                       123     128      +5
applet_names                                        1775    1780      +5
applet_main                                         1076    1080      +4
applet_nameofs                                       538     540      +2
exitcode                                               -       1      +1
------------------------------------------------------------------------------
(add/remove: 3/0 grow/shrink: 6/0 up/down: 1510/0)           Total: 1510 bytes

2 files changed, 10 insertions, 0 deletions

diff --git a/include/applets.h b/include/applets.h
index 90b6e703d..1c654cdd6 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -93,6 +93,7 @@ USE_BZIP2(APPLET(bzip2, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CAL(APPLET(cal, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CAT(APPLET_NOFORK(cat, cat, _BB_DIR_BIN, _BB_SUID_NEVER, cat))
 USE_CATV(APPLET(catv, _BB_DIR_BIN, _BB_SUID_NEVER))
+USE_CHAT(APPLET(chat, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CHATTR(APPLET(chattr, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_CHCON(APPLET(chcon, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CHGRP(APPLET_NOEXEC(chgrp, chgrp, _BB_DIR_BIN, _BB_SUID_NEVER, chgrp))
diff --git a/include/usage.h b/include/usage.h
index d1878827b..0422c7fcf 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -204,6 +204,15 @@ USE_FEATURE_BRCTL_FANCY("\n" \
        "        -e      End each line with $\n" \
        "        -t      Show tabs as ^I\n" \
        "        -v      Don't use ^x or M-x escapes"
+
+#define chat_trivial_usage \
+       "EXPECT [SEND [EXPECT [SEND...]]]"
+#define chat_full_usage \
+       "Useful for interacting with a modem connected to stdin/stdout.\n" \
+       "A script consists of one or more \"expect-send\" pairs of strings,\n" \
+       "each pair is a pair of arguments. Example:\n" \
+       "chat '' ATZ OK ATD123456 CONNECT '' ogin: pppuser word: ppppass '~'" \
+
 #define chattr_trivial_usage \
        "[-R] [-+=AacDdijsStTu] [-v version] files..."
 #define chattr_full_usage \