Add EOVERFLOW error condition

include/errno.h

@@ -78,6 +78,7 @@ extern int errno;		  /* place where the error numbers go */
 #define EIDRM         (_SIGN 43)  /* Identifier removed */
 #define EILSEQ        (_SIGN 44)  /* illegal byte sequence */
 #define EFTYPE        (_SIGN 45)  /* wrong file format or type */
+#define EOVERFLOW     (_SIGN 46)  /* value too large to store in data type */
 
 /* The following errors relate to networking. */
 #define EPACKSIZE     (_SIGN 50)  /* invalid packet size for some protocol */

lib/libc/ansi/errlist.c

@@ -53,7 +53,7 @@ const char *_sys_errlist[] = {
 	"Identifier removed",		/* EIDRM */
 	"Illegal byte sequence",	/* EILSEQ */
 	"Wrong file format or type",	/* EFTYPE */
-	unknown,			/* 46 */
+	"Value too large to be stored in data type",	/* EOVERFLOW */
 	unknown,			/* 47 */
 	unknown,			/* 48 */
 	unknown,			/* 49 */

man/man2/intro.2

@@ -259,6 +259,9 @@ An IPC identifier was removed while the current process was waiting on it.
 A wide character/multibyte character encoding error occurred.
 .It Er 45 EFTYPE Em "Inappropriate file type or format" .
 Attempted a file operation on a file of a type for which it was invalid.
+.It Er 46 EOVERFLOW Em "Value too large to be stored in data type" .
+A numerical result of the function was too large to be stored in the
+caller-provided space.
 .It Er 50 EPACKSIZE Em "Invalid packet size" .
 .It Er 51 ENOBUFS Em "\&No buffer space available" .
 An operation on a socket or pipe was not performed because