Import of unmolested less-290.

1 files changed, 88 insertions, 0 deletions

diff --git a/usr.bin/less/help.c b/usr.bin/less/help.c
new file mode 100644
index 00000000000..27064bb0ecd
--- /dev/null
+++ b/usr.bin/less/help.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 1984,1985,1989,1994,1995  Mark Nudelman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice in the documentation and/or other materials provided with 
+ *    the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN 
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+/*
+ * Display some help.
+ * Just invoke another "less" to display the help file.
+ *
+ * {{ This makes this function very simple, and makes changing the
+ *    help file very easy, but it may present difficulties on
+ *    (non-Unix) systems which do not supply the "system()" function. }}
+ */
+
+#include  "less.h"
+
+extern char *progname;
+
+	public void
+help(nomsg)
+	int nomsg;
+{
+	char *helpfile;
+	char *cmd;
+
+	helpfile = find_helpfile();
+	if (helpfile == NULL)
+	{
+		error("Cannot find help file", NULL_PARG);
+		return;
+	}
+#if !HAVE_SYSTEM
+	/*
+	 * Just examine the help file.
+	 */
+	(void) edit(helpfile);
+#else
+	/*
+	 * Use lsystem() to invoke a new instance of less
+	 * to view the help file.
+	 */
+#if MSOFTC
+	putenv("LESS=-m -H -+E -+s -PmHELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done");
+	cmd = (char *) ecalloc(strlen(helpfile) + strlen(progname) + 3,
+				sizeof(char));
+	sprintf(cmd, "-%s %s", progname, helpfile);
+#else
+	cmd = (char *) ecalloc(strlen(helpfile) + strlen(progname) + 150,
+				sizeof(char));
+#if OS2
+	sprintf(cmd, 
+	 "-%s -m -H -+E -+s \"-PmHELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done \" %s",
+		progname, helpfile);
+#else
+	sprintf(cmd, 
+	 "-%s -m -H -+E -+s '-PmHELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done ' %s",
+		progname, helpfile);
+#endif
+#endif
+	free(helpfile);
+	lsystem(cmd);
+	if (!nomsg)
+		error("End of help", NULL_PARG);
+	free(cmd);
+#endif
+}