Best to show UTC times rather than (unlabelled) local ones

add_off.c

@@ -446,7 +446,7 @@ int process_file( const char *filename, FILE *ofile)
          set_offsets( offsets + i, n_offsets - i);
       }
    if( !ades_found)
-      fprintf( ofile, "COM add_off ver 2024 Aug 11,  run %s", ctime( &t0));
+      fprintf( ofile, "COM add_off ver 2025 Jan 02,  run %.24s UTC\n", asctime( gmtime( &t0)));
    fseek( ifile, 0, SEEK_SET);
    while( fgets( buff, sizeof( buff), ifile))
       if( (jd = get_sat_obs_jd( buff)) <= 0.)    /* not an observation;  */

jpl2b32.cpp

@@ -104,7 +104,7 @@ int main( const int argc, const char **argv)
    fclose( ifile);
    fprintf( ofile, "Ephemeris from JPL Horizons output\n");
    fprintf( ofile, "Created using 'jpl2b32', version %s\n", __DATE__);
-   fprintf( ofile, "Ephemeris converted %s", ctime( &t0));
+   fprintf( ofile, "Ephemeris converted %.24s\n", asctime( gmtime( &t0)));
    printf( "JD0: %f   Step size: %f   %ld steps\n",
                                jd0,  step_size, (long)n_written);
                      /* Seek back to start of file & write corrected hdr: */

jsattest.cpp

@@ -63,7 +63,7 @@ int main( const int argc, const char **argv)
       return( -1);
       }
    printf( "All data in kilometers,  in J2000 ecliptic coords\n");
-   printf( "Compiled %s %s; run %s", __DATE__, __TIME__, ctime( &t0));
+   printf( "Compiled %s %s; run %.24s\n", __DATE__, __TIME__, asctime( gmtime( &t0)));
    printf( "   JDE         dx        dy        dz             ");
    printf( "x          y          z         radial    along\n");
    while( fgets( buff, sizeof( buff), ifile))

mpc_code.cpp

@@ -836,8 +836,8 @@ int main( const int argc, const char **argv)
                google_map_links = true;
                google_offset = 3;
                while( fgets( buff, sizeof( buff), hdr_ifile))
-                  if( strstr( buff, "%s"))
-                     printf( buff, ctime( &t0));
+                  if( strstr( buff, "%.24s"))
+                     printf( buff, asctime( gmtime( &t0)));
                   else if( *buff == '#')
                      {
                      if( strstr( ifilename, "rovers") &&

mpc_hdr.htm

@@ -12,7 +12,7 @@
 
 <h1> MPC observatory codes </h1>
 
-<p> <i> Created %s</i> </p>
+<p> <i> Created %.24s UTC</i> </p>
 
 <p> <a href='https://www.google.com/maps/d/edit?mid=1aHxNHag3UjO9siiciGya38yIlp2Shtbj&usp=sharing'>
 Click here for a G__gle Map showing all observatory codes</a> </p>

them_cat.c

@@ -65,7 +65,7 @@ int main( const int argc, const char **argv)
       if( !memcmp( buff, "# Ephemeris end:", 16))
          strlcpy_error( buff, new_end);
       if( !memcmp( buff, "# Last updated with", 19))
-         strlcpy_err( buff + 42, ctime( &t0), sizeof( buff) - 42);
+         strlcpy_err( buff + 42, asctime( gmtime( &t0)), sizeof( buff) - 42);
 
       fputs( buff,  temp_file);
       if( !memcmp( buff, "# MJD ", 6) && atof( buff + 6) == jd0_new - 1.)