Interface cleanup: Symlink handling & docs

This removes the ability to start nvim via the following aliases in
favor of just using their command line arguments:

ex        vim -e
exim      vim -E
view      vim -R
gvim      vim -g
gex       vim -eg
gview     vim -Rg
rvim      vim -Z
rview     vim -RZ
rgvim     vim -gZ
rgview    vim -RgZ

This also removes Vi mode (-v) for consistency. From ':help -v':

    -v  Start Ex in Vi mode.  Only makes a difference when the
    executable is called "ex" or "gvim".  For gvim the GUI is not
    started if possible.

5 files changed, 13 insertions, 83 deletions

diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index c4abcd77b1..c0b688e6ef 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -213,7 +213,7 @@ open_buffer (
    * So the modelines have priority over auto commands.
    */
   /* When reading stdin, the buffer contents always needs writing, so set
-   * the changed flag.  Unless in readonly mode: "ls | gview -".
+   * the changed flag.  Unless in readonly mode: "ls | nvim -R -".
    * When interrupted and 'cpoptions' contains 'i' set changed flag. */
   if ((got_int && vim_strchr(p_cpo, CPO_INTMOD) != NULL)
       || modified_was_set               /* ":set modified" used in autocmd */
diff --git a/src/nvim/ex_cmds.c b/src/nvim/ex_cmds.c
index e98032da5c..a47b303a4a 100644
--- a/src/nvim/ex_cmds.c
+++ b/src/nvim/ex_cmds.c
@@ -853,7 +853,7 @@ void do_bang(int addr_count, exarg_T *eap, int forceit, int do_in, int do_out)
   int scroll_save = msg_scroll;
 
   /*
-   * Disallow shell commands for "rvim".
+   * Disallow shell commands in restricted mode (-Z)
    * Disallow shell commands from .exrc and .vimrc in current directory for
    * security reasons.
    */
@@ -1217,7 +1217,7 @@ do_shell (
   int save_nwr;
 
   /*
-   * Disallow shell commands for "rvim".
+   * Disallow shell commands in restricted mode (-Z)
    * Disallow shell commands from .exrc and .vimrc in current directory for
    * security reasons.
    */
@@ -3378,7 +3378,7 @@ void ex_z(exarg_T *eap)
 int check_restricted(void)
 {
   if (restricted) {
-    EMSG(_("E145: Shell commands not allowed in rvim"));
+    EMSG(_("E145: Shell commands not allowed in restricted mode"));
     return TRUE;
   }
   return FALSE;
diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index 4e835cc43a..fa6021075d 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -5375,9 +5375,7 @@ static void ex_hide(exarg_T *eap)
  */
 static void ex_stop(exarg_T *eap)
 {
-  /*
-   * Disallow suspending for "rvim".
-   */
+  // Disallow suspending in restricted mode (-Z)
   if (!check_restricted()) {
     if (!eap->forceit) {
       autowrite_all();
diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index b15db61f99..d7087ee928 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -601,7 +601,7 @@ EXTERN volatile int full_screen INIT(= FALSE);
  * otherwise only writing some messages */
 
 EXTERN int restricted INIT(= FALSE);
-/* TRUE when started as "rvim" */
+// TRUE when started in restricted mode (-Z)
 EXTERN int secure INIT(= FALSE);
 /* non-zero when only "safe" commands are
  * allowed, e.g. when sourcing .exrc or .vimrc
diff --git a/src/nvim/main.c b/src/nvim/main.c
index 897f251bb3..a4f430e811 100644
--- a/src/nvim/main.c
+++ b/src/nvim/main.c
@@ -204,11 +204,9 @@ int main(int argc, char **argv)
   // Check if we have an interactive window.
   check_and_set_isatty(&params);
 
-  /*
-   * Figure out the way to work from the command name argv[0].
-   * "view" sets "readonlymode", "rvim" sets "restricted", etc.
-   */
-  parse_command_name(&params);
+  // Get the name with which Nvim was invoked, with and without path.
+  set_vim_var_string(VV_PROGPATH, (char_u *)argv[0], -1);
+  set_vim_var_string(VV_PROGNAME, path_tail((char_u *)argv[0]), -1);
 
   /*
    * Process the command line arguments.  File names are put in the global
@@ -820,69 +818,8 @@ static void init_locale(void)
   }
   TIME_MSG("locale set");
 }
-
 #endif
 
-/*
- * Check for: [r][g][vi|vim|view][ex[im]]
- * If the executable name starts with "r" we disable shell commands.
- * If the next character is "g" we run the GUI version.
- * If the next characters are "view" we start in readonly mode.
- * If the next characters are "ex" we start in Ex mode.  If it's followed
- * by "im" use improved Ex mode.
- */
-static void parse_command_name(mparm_T *parmp)
-{
-  char_u      *initstr;
-
-  initstr = path_tail((char_u *)parmp->argv[0]);
-
-  set_vim_var_string(VV_PROGNAME, initstr, -1);
-  set_vim_var_string(VV_PROGPATH, (char_u *)parmp->argv[0], -1);
-
-  if (parse_string(&initstr, "editor", 6))
-    return;
-
-  if (parse_char_i(&initstr, 'r'))
-    restricted = TRUE;
-
-  /* "gvim" starts the GUI.  Also accept "Gvim" for MS-Windows. */
-  if (parse_char_i(&initstr, 'g'))
-    main_start_gui();
-
-  if (parse_string(&initstr, "view", 4)) {
-    readonlymode = TRUE;
-    curbuf->b_p_ro = TRUE;
-    p_uc = 10000;                       /* don't update very often */
-  } else {
-    parse_string(&initstr, "vim", 3);   /* consume "vim" if it's there */
-  }
-
-  if (parse_string(&initstr, "ex", 2)) {
-    if (parse_string(&initstr, "im", 2))
-      exmode_active = EXMODE_VIM;
-    else
-      exmode_active = EXMODE_NORMAL;
-  }
-}
-
-static bool parse_char_i(char_u **input, char val)
-{
-  if (TOLOWER_ASC(**input) == val) {
-    *input += 1;  /* or (*input)++ WITH parens */
-    return true;
-  }
-  return false;
-}
-
-static bool parse_string(char_u **input, char *val, int len)
-{
-  if (STRNICMP(*input, val, len) == 0) {
-    *input += len;
-    return true;
-  }
-  return false;
-}
 
 /*
  * Scan the command line arguments.
@@ -1134,10 +1071,6 @@ static void command_line_scan(mparm_T *parmp)
           }
           break;
 
-        case 'v':                 /* "-v"  Vi-mode (as if called "vi") */
-          exmode_active = 0;
-          break;
-
         case 'w':                 /* "-w{number}"	set window height */
           /* "-w {scriptout}"	write to script */
           if (vim_isdigit(((char_u *)argv[0])[argv_idx])) {
@@ -2034,13 +1967,12 @@ static void usage(void)
 #if !defined(UNIX)
   mch_msg(_("  --literal             Don't expand wildcards\n"));
 #endif
-  mch_msg(_("  -v                    Vi mode (like \"vi\")\n"));
-  mch_msg(_("  -e                    Ex mode (like \"ex\")\n"));
+  mch_msg(_("  -e                    Ex mode\n"));
   mch_msg(_("  -E                    Improved Ex mode\n"));
-  mch_msg(_("  -s                    Silent (batch) mode (only for \"ex\")\n"));
+  mch_msg(_("  -s                    Silent (batch) mode (only for ex mode)\n"));
   mch_msg(_("  -d                    Diff mode\n"));
-  mch_msg(_("  -R                    Readonly mode (like \"view\")\n"));
-  mch_msg(_("  -Z                    Restricted mode (like \"rvim\")\n"));
+  mch_msg(_("  -R                    Readonly mode\n"));
+  mch_msg(_("  -Z                    Restricted mode\n"));
   mch_msg(_("  -m                    Modifications (writing files) not allowed\n"));
   mch_msg(_("  -M                    Modifications in text not allowed\n"));
   mch_msg(_("  -b                    Binary mode\n"));