Improve documentation

diff --git a/utils/sterm.c b/utils/sterm.c
index ee7f8d70433e64d47db376efa2925dd188bbd5ee..305a9855dd0998339f289210adb160dc006f1e8b 100644 (file)
--- a/utils/sterm.c
+++ b/utils/sterm.c
@@ -106,6 +106,17 @@ void exit_on_escapeseq(const char *buf, int len)
        }
 }
 
        }
 }
 

+void usage(const char* argv0)
+{
+       fprintf(stderr, "Usage: %s [options] <device>\n", argv0);
+       fprintf(stderr, "Options:\n");
+       fprintf(stderr, "  -d [+|-] create short positive/negative pulse on DTR\n");
+       fprintf(stderr, "  -e       ignore '~.' escape sequence\n");
+       fprintf(stderr, "  -n       do not switch the device to raw mode\n");
+       fprintf(stderr, "  -r [+|-] create short positive/negative pulse on RTS\n");
+       fprintf(stderr, "  -s <baudrate>\n");
+       fprintf(stderr, "  -v       verbose\n");
+}

 
 int main(int argc, char *argv[])
 {
 
 int main(int argc, char *argv[])
 {


@@ -163,7 +174,7 @@ int main(int argc, char *argv[])
                        verbose = true;
                        break;
                default: /* '?' */
                        verbose = true;
                        break;
                default: /* '?' */

-                       fprintf(stderr, "Usage: %s [-s baudrate] [-v] <device>\n", argv[0]);
+                       usage(argv[0]);

                        exit(1);
                }
        }
                        exit(1);
                }
        }


@@ -173,6 +184,7 @@ int main(int argc, char *argv[])
 
        if (!dev) {
                fprintf(stderr, "No device specified\n");
 
        if (!dev) {
                fprintf(stderr, "No device specified\n");

+               usage(argv[0]);

                exit(1);
        }
 
                exit(1);
        }