1 files changed, 64 insertions, 0 deletions
diff --git a/lib/libI77/due.c b/lib/libI77/due.c
new file mode 100644
index 0000000..33ee02c
--- /dev/null
+++ b/lib/libI77/due.c
@@ -0,0 +1,64 @@
+#include "f2c.h"
+#include "fio.h"
+
+#ifdef KR_headers
+c_due(a) cilist *a;
+#else
+c_due(cilist *a)
+#endif
+{
+	if(!f__init) f_init();
+	if(a->ciunit>=MXUNIT || a->ciunit<0)
+		err(a->cierr,101,"startio");
+	f__sequential=f__formatted=f__recpos=0;
+	f__external=1;
+	f__curunit = &f__units[a->ciunit];
+	f__elist=a;
+	if(f__curunit->ufd==NULL && fk_open(DIR,UNF,a->ciunit) ) err(a->cierr,104,"due");
+	f__cf=f__curunit->ufd;
+	if(f__curunit->ufmt) err(a->cierr,102,"cdue")
+	if(!f__curunit->useek) err(a->cierr,104,"cdue")
+	if(f__curunit->ufd==NULL) err(a->cierr,114,"cdue")
+	(void) fseek(f__cf,(long)(a->cirec-1)*f__curunit->url,SEEK_SET);
+	f__curunit->uend = 0;
+	return(0);
+}
+#ifdef KR_headers
+integer s_rdue(a) cilist *a;
+#else
+integer s_rdue(cilist *a)
+#endif
+{
+	int n;
+	if(n=c_due(a)) return(n);
+	f__reading=1;
+	if(f__curunit->uwrt && f__nowreading(f__curunit))
+		err(a->cierr,errno,"read start");
+	return(0);
+}
+#ifdef KR_headers
+integer s_wdue(a) cilist *a;
+#else
+integer s_wdue(cilist *a)
+#endif
+{
+	int n;
+	if(n=c_due(a)) return(n);
+	f__reading=0;
+	if(f__curunit->uwrt != 1 && f__nowwriting(f__curunit))
+		err(a->cierr,errno,"write start");
+	return(0);
+}
+integer e_rdue(Void)
+{
+	if(f__curunit->url==1 || f__recpos==f__curunit->url)
+		return(0);
+	(void) fseek(f__cf,(long)(f__curunit->url-f__recpos),SEEK_CUR);
+	if(ftell(f__cf)%f__curunit->url)
+		err(f__elist->cierr,200,"syserr");
+	return(0);
+}
+integer e_wdue(Void)
+{
+	return(e_rdue());
+}