default preloaded guess to explicit &dumpname if given (from IgorL)

git-svn-id: svn://tug.org/texlive/trunk@49433 c570f23f-e606-0410-a88d-b1316a301751

2 files changed, 19 insertions, 3 deletions

diff --git a/Build/source/texk/web2c/lib/ChangeLog b/Build/source/texk/web2c/lib/ChangeLog
index 66a33f23c4d..1e7b8fe97ba 100644
--- a/Build/source/texk/web2c/lib/ChangeLog
+++ b/Build/source/texk/web2c/lib/ChangeLog
@@ -1,3 +1,10 @@
+2018-12-17  Igor Liferenko  <igor.liferenko@gmail.com>
+
+	* texmfmp.c (maininit): default to guessing an explicit &dumpname
+	as the "preloaded" (not really) format, if one was specified.
+	tex-k msgs of 23 Sep 2018 12:13:06, 23 Sep 2018 18:36:52.
+	(With comment and formatting tinkering from karl.)
+
 2018-12-17  Andreas Scherer  <https://ascherer.github.io>
 
 	* printversion.c (printversionandexit): Search for PROGNAME
diff --git a/Build/source/texk/web2c/lib/texmfmp.c b/Build/source/texk/web2c/lib/texmfmp.c
index 329a3f9222d..94232cff078 100644
--- a/Build/source/texk/web2c/lib/texmfmp.c
+++ b/Build/source/texk/web2c/lib/texmfmp.c
@@ -783,7 +783,7 @@ maininit (int ac, string *av)
   xputenv ("engine", TEXMFENGINENAME);
   
   /* Were we given a simple filename? */
-  main_input_file = get_input_file_name();
+  main_input_file = get_input_file_name ();
 
 #ifdef WIN32
   if (main_input_file == NULL) {
@@ -853,7 +853,9 @@ maininit (int ac, string *av)
     translate_filename = default_translate_filename;
   }
   /* If we're preloaded, I guess everything is set up.  I don't really
-     know any more, it's been so long since anyone preloaded.  */
+     know any more, it's been so long since anyone truly preloaded.  We
+     still use the word "preloaded" in the messages through (via the
+     original .web sources), at Knuth's request.  */
   if (readyalready != 314159) {
     /* The `ini_version' variable is declared/used in the change files.  */
     boolean virversion = false;
@@ -873,9 +875,16 @@ maininit (int ac, string *av)
 #endif /* TeX */
     }
 
+    /* If run like `tex \&foo', reasonable to guess "foo" as the fmt name.  */
+    if (!main_input_file) {
+      if (argv[1] && *argv[1] == '&') {
+        dump_name = argv[1] + 1;
+      }
+    }
+
     if (!dump_name) {
       /* If called as *vir{mf,tex,mpost} use `plain'.  Otherwise, use the
-         name we were invoked under.  */
+         name we were invoked under as our best guess.  */
       dump_name = (virversion ? "plain" : kpse_program_name);
     }
   }