1 files changed, 65 insertions, 0 deletions
diff --git a/sys/etc/onentry.x b/sys/etc/onentry.x
new file mode 100644
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+++ b/sys/etc/onentry.x
@@ -0,0 +1,65 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<knet.h>
+include	<error.h>
+include	<clset.h>
+include	<fset.h>
+
+define	NFD		2
+
+# ONENTRY -- Default procedure called by the IRAF Main during process startup,
+# before entering the interpreter loop.  If desired the user can supply their
+# own ONENTRY procedure; this will be used instead of the system default if
+# specified on the link line before the iraf libraries are searched.
+# This procedure is a no-op for a connected or host process.  For a detached
+# process the default action is to redirect the standard input to the bkgfile,
+# which is assumed to be a text file containing commands to be executed by
+# the Main.
+#
+# The basic host calling sequence for an iraf process is as follows:
+#
+#	 x_file.e [-c | -d bkgfile ] [ command ]
+#
+# This is parsed by the zmain (host level main), returning the process type
+# in PRTYPE, the bkgfile string in BKGFILE if the process type is detached,
+# and anything remaining on the command line in CMD.  If a custom onentry
+# procedure is used CMD can be anything; all the iraf main does is concatenate
+# the arguments into a string and pass it to the onentry procedure as CMD.
+
+int procedure onentry (prtype, bkgfile, cmd)
+
+int	prtype			#I process type (connected, detached, host)
+char	bkgfile[ARB]		#I osfn of bkg file, if detached process
+char	cmd[ARB]		#I command argument string, if any
+
+char	osfn[SZ_FNAME]
+int	chan, loc_zgettx, i, fd[NFD]
+data	fd[1] /CLIN/, fd[2] /STDIN/
+extern	zgettx()
+
+begin
+	if (prtype == PR_DETACHED) {
+	    # Open the bkgfile and connect it to CLIN and STDIN.  The stdin
+	    # supplied by the process main is not used in this mode.
+	    # We assume that no i/o has yet occurred on either file.  Note
+	    # that we do not wish to use FREDIR as that would preclude
+	    # redirection on the command line.
+
+	    call strpak (bkgfile, osfn, SZ_FNAME)
+	    call zopntx (osfn, READ_ONLY, chan)
+	    if (chan == ERR)
+		call sys_panic (EA_FATAL, "Cannot open bkgfile")
+	    call zlocpr (zgettx, loc_zgettx)
+
+	    do i = 1, NFD {
+		call fseti (fd[i], F_CHANNEL, chan)
+		call fseti (fd[i], F_DEVICE, loc_zgettx)
+		call fseti (fd[i], F_TYPE, TEXT_FILE)
+	    }
+	}
+
+	# If PR_EXIT is returned the interpreter loop is bypassed and process
+	# shutdown occurs immediately.
+
+	return (PR_NOEXIT)
+end