From 924bf775f7824eb3564bf71cc9fab26a7d217899 Mon Sep 17 00:00:00 2001
From: Bill-Gray <pluto@projectpluto.com>
Date: Wed, 29 Mar 2023 10:24:53 -0400
Subject: [PATCH] 'sat_eph' now assumes reasonable default values for start
 time (now),  number of ephemeris steps (20),  and step size (one hour).  It
 also defaults to rounding to the nearest ephemeris step size,  and is
 slightly better about outputting an error message when errors happen.

---
 sat_eph.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/sat_eph.c b/sat_eph.c
index ee88e47..be5df3e 100644
--- a/sat_eph.c
+++ b/sat_eph.c
@@ -320,6 +320,8 @@ int generate_artsat_ephems( const char *path_to_tles, const ephem_t *e)
    int is_in_range = 0, id_matches = 1, start_line = 0;
 
    snprintf( buff, sizeof( buff), "%s/%s", path_to_tles, tle_list_filename);
+   if( verbose > 1)
+      printf( "Opening '%s'\n", buff);
    ifile = fopen( buff, "rb");
    if( !ifile)
       {
@@ -469,16 +471,19 @@ int dummy_main( const int argc, const char **argv)
 {
    int i;
    ephem_t e;
-   bool round_to_nearest_step = false;
+   bool round_to_nearest_step = true;
    const char *mpc_code = "500";
    const char *override_tle_filename = NULL;
 
-   if( argc < 3)
+   if( argc < 2)
       {
       error_help( );
       return( 0);
       }
    memset( &e, 0, sizeof( ephem_t));
+   e.jd_start = current_jd( );
+   e.n_steps = 20;
+   e.step_size = 1. / 24.;
    for( i = 1; i < argc; i++)
       if( argv[i][0] == '-' && argv[i][1])
          {
@@ -496,13 +501,8 @@ int dummy_main( const int argc, const char **argv)
                override_tle_filename = arg;
                break;
             case 't':
-               {
-               const double jan_1970 = 2440587.5;
-               const double curr_jd = jan_1970 + (double)time( NULL) / (double)seconds_per_day;
-
-               e.jd_start = get_time_from_string( curr_jd, arg, FULL_CTIME_YMD, NULL);
+               e.jd_start = get_time_from_string( e.jd_start, arg, FULL_CTIME_YMD, NULL);
                break;
-               }
             case 'n':
                e.n_steps = atoi( arg);
                break;