Network Working Group J. Postel Request for Comments: 899 A. Westine ISI May 1984 Requests For Comments Summary
Notes: 800-899
Status of this Memo
This RFC is a slightly annotated list of the 100 RFCs from RFC 800
through RFC 899. This is a status report on these RFCs.
RFC Author Date Title
--- ------ ---- -----
899 Postel Apr 84 Requests For Comments Summary
This memo.
898 Hinden Apr 84 Gateway Special Interest Group Meeting Notes
This memo is a report on the Gateway Special Interest Group Meeting
that was held at ISI on 28 and 29 February 1984. Robert Hinden of
BBNCC chaired, and Jon Postel of ISI hosted the meeting.
Approximately 35 gateway designers and implementors attended. These notes are based on the recollections of Jon Postel and Mike Muuss.
Under each topic area are Jon Postel’s brief notes, and additional
details from Mike Muuss. This memo is a report on a meeting. No
conclusions, decisions, or policy statements are documented in this
note.
897 Postel Feb 84 Domain Name System Implementation
Schedule
This memo is a policy statement on the implementation of the Domain
Style Naming System in the Internet. This memo is a partial update
of RFC 881. The intent of this memo is to detail the schedule for
the implementation for the Domain Style Naming System. The names of hosts will be changed to domain style names. Hosts will begin to use domain style names on 14-Mar-84, and the use of old style names will be completely phased out before 2-May-84. This applies to both the
ARPA research hosts and the DDN operational hosts. This is an
official policy statement of the ICCB and the DARPA.
Postel & Westine [page 1]
896 Nagle Jan 84 Congestion Control in IP/TCP
Internetworks
This memo discusses some aspects of congestion control in IP/TCP
Internetworks. It is intended to stimulate thought and further
discussion of this topic. While some specific suggestions are made
for improved congestion control implementation, this memo does not
specify any standards.
895 Postel Apr 84 A Standard for the Transmission of
IP Datagrams over Experimental Ethernet Networks
This RFC specifies a standard method of encapsulating Internet
Protocol (IP) datagrams on an Experimental Ethernet. This RFC
specifies a standard protocol for the ARPA Internet community.
894 Hornig Apr 84 A Standard for the Transmission of
IP Datagrams over Ethernet Networks
This RFC specifies a standard method of encapsulating Internet
Protocol (IP) datagrams on an Ethernet. This RFC specifies a
standard protocol for the ARPA-Internet community.
893 Leffler Apr 84 Trailer Encapsulations
This RFC discusses the motivation for use of "trailer encapsulations" on local-area networks and describes the implementation of such an
encapsulation on various media. This document is for information
only. This is NOT an official protocol for the ARPA Internet
community.
892 ISO Dec 83 ISO Transport Protocol Specification
This is a draft version of the transport protocol being standardized by the ISO. This version also appeared in the ACM SIGCOMM Computer
Communication Review (V.12, N.3-4) July-October 1982. This version
is now out of date.
891 Mills Dec 83 DCN Local-Network Protocols
This RFC provides a description of the DCN protocols for maintaining connectivity, routing, and clock information in a local network.
These procedures may be of interest to the designers and implementers of other local networks.
Postel & Westine [page 2]
890 Postel Feb 84 Exterior Gateway Protocol
Implementation Schedule
This memo is a policy statement on the implementation of the Exterior Gateway Protocol in the Internet. This is an official policy
statement of ICCB and DARPA. After 1-Aug-84 there shall be no dumb
gateways in the Internet. Every gateway must be a member of some
autonomous system. Some gateway of each autonomous system must
exchange routing information with some gateway of the core autonomous system using the Exterior Gateway Protocol.
889 Mills Dec 83 Internet Delay Experiments
This memo reports on some measurements of round-trip times in the
Internet and suggests some possible improvements to the TCP
retransmission timeout calculation. This memo is both a status
report on the Internet and advice to TCP implementers.
888 Seamonson Jan 84 "Stub" Exterior Gateway Protocol
This RFC describes the Exterior Gateway Protocol used to connect Stub Gateways to an Autonomous System of core Gateways. This document
specifies the working protocol, and defines an ARPA official
protocol. All implementers of Gateways should carefully review this document.
887 Accetta Dec 83 Resource Location Protocol
This RFC specifies a draft standard for the ARPA Internet community. It describes a resource location protocol for use in the ARPA
Internet. It is most useful on networks employing technologies which support some method of broadcast addressing, however it may also be
used on other types of networks. For maximum benefit, all hosts
which provide significant resources or services to other hosts on the Internet should implement this protocol. Hosts failing to implement the Resource Location Protocol risk being ignored by other hosts
which are attempting to locate resources on the Internet.
886 Rose Dec 83 Proposed Standard for Message Header
Munging
This RFC specifies a draft standard for the ARPA Internet community. It describes the rules to be used when transforming mail from the
conventions of one message system to those of another message system. In particular, the treatment of header fields, and recipient
addresses is specified.
Postel & Westine [page 3]
885 Postel Dec 83 Telnet End of Record Option
This RFC specifies a standard for the ARPA Internet community. It
specifies a method for marking the end of records in data transmitted on Telnet connections.
884 Solomon Dec 83 Telnet Terminal Type Option
This RFC specifies a standard for the ARPA Internet community. It
specifies a method for exchanging terminal type information in the
Telnet protocol.
883 Mockapetris Nov 83 Domain Names - Implementation and
Specification
This RFC discusses the implementation of domain name servers and
resolvers, specifies the format of transactions, and discusses the
use of domain names in the context of existing mail systems and other network software.
882 Mockapetris Nov 83 Domain Names - Concepts and Facilities This RFC introduces domain style names, their use for ARPA Internet
mail and host address support, and the protocol and servers used to
implement domain name facilities.
881 Postel Nov 83 The Domain Names Plan and Schedule
This RFC outlines a plan and schedule for the implementation of
domain style names throughout the DDN/ARPA Internet community. The
introduction of domain style names will impact all hosts on the
DDN/ARPA Internet.
880 Reynolds Oct 83 Official Protocols
This RFC identifies the documents specifying the official protocols
used in the ARPA Internet. Annotations identify any revisions or
changes planned. Obsoletes RFC 840.
879 Postel Nov 83 The TCP Maximum Segment Size and
Related Topics
This RFC discusses the TCP Maximum Segment Size Option and related
topics. The purposes is to clarify some aspects of TCP and its
interaction with IP. This memo is a clarification to the TCP
specification, and contains information that may be considered as
"advice to implementers".
Postel & Westine [page 4]
878 Malis Dec 83 The ARPANET 1822L Host Access Protocol This RFC specifies the ARPANET 1822L Host Access Protocol, which is a successor to the existing 1822 Host Access Protocol. The 1822L
procedure allows ARPANET hosts to use logical identifiers as well as 1822 physical interface identifiers to address each other.
877 Korb Sep 83 A Standard for the Transmission of IP
Datagrams Over Public Data Networks
This RFC specifies a standard adopted by CSNET, the VAN gateway, and other organizations for the transmission of IP datagrams over the
X.25-based public data networks.
876 Smallberg Sep 83 Survey of SMTP Implementations
This RFC is a survey of implementation status. It does not specify
an official protocol, but rather notes the status of implementation
of aspects of a protocol. It is expected that the status of the
hosts reported on will change. This information must be treated as a snapshot of the state of these implemetations.
875 Padlipsky Sep 82 Gateways, Architectures, and Heffalumps This RFC is a discussion about the role of gateways in an
internetwork, especially the problems of translating or mapping
protocols between different protocol suites. The discussion notes
possible functionality mis-matches, undesirable routing "singularity points", flow control issues, and high cost of translating gateways. Originally published as M82-51 by the MITRE Corporation, Bedford,
Massachusetts.
874 Padlipsky Sep 82 A Critique of X.25
This RFC is an analysis of X.25 pointing out some problems in the
conceptual model, particularly the conflict between the interface
aspects and the end-to-end aspects. The memo also touches on
security, and implementation issues. Originally published as M82-50 by the MITRE Corporation, Bedford, Massachusetts.
873 Padlipsky Sep 82 The Illusion of Vendor Support
This memo takes issue with the claim that international standards in computer protocols presently provide a basis for low cost vendor
supported protocol implementations. Originally published as M82-49
by the MITRE Corporation, Bedford, Massachusetts.
Postel & Westine [page 5]
872 Padlipsky Sep 82 TCP-ON-A-LAN
This memo attacks the notion that TCP cannot be appropriate for use
on a Local Area Network. Originally published as M82-48 by the MITRE Corporation, Bedford Massachusetts.
871 Padlipsky Sep 82 A Perspective on the Arpanet Reference Model
This RFC is primarily intended as a perspective on the ARM and points out some of the differences between the ARM and the ISORM which were expressed by members in NWG general meetings, NWG protocol design
committee meetings, the ARPA Internet Working Group, and private
conversations over the intervening years. Originally published as
M82-47 by the MITRE Corporation, Bedford, Massachusetts.
870 Reynolds Oct 83 Assigned Numbers
This RFC documents the list of numbers assigned for networks,
protocols, etc. Obsoletes RFCs 820, 790, 776, 770, 762, 758, 755,
750, 739, 604.
869 Hinden Dec 83 A Host Monitoring Protocol
This RFC specifies the Host Monitoring Protocol used to collect
information from various types of hosts in the Internet. Designers
of Internet communications software are encouraged to consider this
protocol as a means of monitoring the behavior of their creations. 868 Postel May 83 Time Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Time Protocol are
expected to adopt and implement this standard. This protocol
provides a site-independent, machine readable date and time. The
Time service sends back to the originating source the time in seconds since midnight on January first 1900.
867 Postel May 83 Daytime Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Daytime Protocol are expected to adopt and implement this standard. The Daytime service
simply sends the current date and time as a character string without regard to the input.
Postel & Westine [page 6]
866 Postel May 83 Active Users
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement an Active Users
Protocol are expected to adopt and implement this standard. The
Active Users service simply sends a list of the currently active
users on the host without regard to the input.
865 Postel May 83 Quote of the Day Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Quote of the Day
Protocol are expected to adopt and implement this standard. The
Quote of the Day service simply sends a short message without regard to the input.
864 Postel May 83 Character Generator Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Character Generator
Protocol are expected to adopt and implement this standard. The
Character Generator service simply sends data without regard to the
input.
863 Postel May 83 Discard Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Discard Protocol are expected to adopt and implement this standard. The Discard service
simply throws away any data it receives.
862 Postel May 83 Echo Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet that choose to implement a Echo Protocol are
expected to adopt and implement this standard. The Echo service
simply sends back to the originating source any data it receives.
861 Postel May 83 Telnet Extended Options - List Option
This Telnet Option provides a mechanism for extending the set of
possible options. This RFC specifies a standard for the ARPA
Internet community. Hosts on the ARPA Internet are expected to adopt and implement this standard. Obsoletes NIC 16239.
Postel & Westine [page 7]
860 Postel May 83 Telnet Timing Mark Option
This Telnet Option provides a way to check the roundtrip path between two Telnet modules. This RFC specifies a standard for the ARPA
Internet community. Hosts on the ARPA Internet are expected to adopt and implement this standard. Obsoletes NIC 16238.
859 Postel May 83 Telnet Status Option
This Telnet Option provides a way to determine the other Telnet
module’s view of the status of options. This RFC specifies a
standard for the ARPA Internet community. Hosts on the ARPA Internet are expected to adopt and implement this standard. Obsoletes RFC 651 (NIC 31154).
858 Postel May 83 Telnet Suppress Go Ahead Option
This Telnet Option disables the exchange of go-ahead signals between the Telnet modules. This RFC specifies a standard for the ARPA
Internet community. Hosts on the ARPA Internet are expected to adopt and implement this standard. Obsoletes NIC 15392.
857 Postel May 83 Telnet Echo Option
This Telnet Option enables remote echoing by the other Telnet module. This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet are expected to adopt and implement this
standard. Obsoletes NIC 15390.
856 Postel May 83 Telnet Binary Transmission
This Telnet Option enables a binary data mode between the Telnet
modules. This RFC specifies a standard for the ARPA Internet
community. Hosts on the ARPA Internet are expected to adopt and
implement this standard. Obsoletes NIC 15389.
855 Postel May 83 Telnet Option Specifications
This memo specifies the general form for Telnet options and the
directions for their specification. This RFC specifies a standard
for the ARPA Internet community. Hosts on the ARPA Internet are
expected to adopt and implement this standard. Obsoletes RFC 651,
NIC 18640.
Postel & Westine [page 8]
854 Postel May 83 Telnet Protocol Specifications
This is the specification of the Telnet protocol used for remote
terminal access in the ARPA Internet. The purpose of the TELNET
Protocol is to provide a fairly general, bi-directional, eight-bit
byte oriented communications facility. Its primary goal is to allow a standard method of interfacing terminal devices and
terminal-oriented processes to each other. It is envisioned that the protocol may also be used for terminal-terminal communication
("linking") and process-process communication (distributed
computation). This RFC specifies a standard for the ARPA Internet
community. Hosts on the ARPA Internet are expected to adopt and
implement this standard. Obsoletes NIC 18639.
853 Not issued yet.
852 Malis Apr 83 The ARPANET Short Blocking Feature
This RFC specifies the ARPANET Short Blocking Feature, which will
allow ARPANET hosts to optionally shorten the IMP’s host blocking
timer. This Feature is a replacement of the ARPANET non-blocking
host interface, which was never implemented, and will be available to hosts using either the 1822 or 1822L Host Access Protocol. This RFC is also being presented as a solicitation of comments on the Short
Blocking Feature, especially from host network software implementers and maintainers.
851 Malis Apr 83 The ARPANET 1822L Host Access Protocol This RFC specifies the ARPANET 1822L Host Access Protocol, which is a successor to the existing 1822 Host Access Protocol. 1822L allows
ARPANET hosts to use logical names as well as 1822’s physical port
locations to address each other. This RFC is also being presented as a solicitation of comments on 1822L, especially from host network
software implementers and maintainers. Obsoletes RFC 802.
850 Horton Jun 83 Standard for Interchange of USENET
Messages
This memo is distributed as an RFC only to make this information
easily accessible to researchers in the ARPA community. It does not specify an Internet standard. This RFC defines the standard format
for interchange of Network News articles among USENET sites. It
describes the format for articles themselves, and gives partial
standards for transmission of news. The news transmission is not
entirely standardized in order to give a good deal of flexibility to the individual hosts to choose transmission hardware and software,
whether to batch news and so on.
Postel & Westine [page 9]
849 Crispin May 83 Suggestions for Improved Host Table
Distribution
This RFC actually is a request for comments. The issue dealt with is that of a naming registry update procedure, both as exists currently and what could exist in the future. None of the proposed solutions
are intended as standards at this time; rather it is hoped that a
general consensus will emerge as the appropriate solution, leaving
eventually to the adoption of standards.
848 Smallberg Mar 83 Who provides the "Little" TCP Services? This RFC lists those hosts which provide any of these "little" TCP
services: The list of hosts were taken from the NIC hostname table
of 24-Feb-83. The tests were run on February 23 and 24, and March 3 and 5 from ISI-VAXA.ARPA.
847 Westine Feb 83 Summary of Smallberg Surveys
This is a summary of the surveys of Telnet, FTP and Mail (SMTP)
servers conducted by David Smallberg in December 1982, January and
February 1983 as reported in RFC 832-843, 845-846. This memo
extracts the number of hosts that accepted the connection to their
server for each of Telnet, FTP, and SMTP, and compares it to the
total host in the Internet (not counting TACs or ECHOS).
846 Smallberg Feb 83 Who Talks TCP? -- Survey of 22 February 1983
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 18-Feb-83. The tests were run on 22-Feb-83 from ISI-VAXA.ARPA.
845 Smallberg Feb 83 Who Talks TCP? -- Survey of 15 February 1983
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 3-Feb-83. The tests were run on 15-Feb-83 from ISI-VAXA.ARPA.
Postel & Westine [page 10]
844 Clements Feb 83 Who Talks ICMP, too? Survey of 18
February 1983
This survey determines how many hosts are able to respond to TELENET connections from a user at a class C site. This requires, in
addition to IP and TCP, participation in gateway routing via ICMP and handling of Class C addresses. The list of hosts was taken from RFC 843, extracting only those hosts which are listed there as accepting TELNET connection. The tests were run on 18-Feb-83.
843 Smallberg Feb 83 Who Talks TCP? -- Survey of 8 February 1983
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 3-Feb-83. The tests were run on 8-Feb-83
and on 9-Feb-83 from ISI-VAXA.ARPA.
842 Smallberg Feb 83 Who Talks TCP? -- Survey of 1 February 1983
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 28-Jan-83. The tests were run on 1-Feb-83 and on 2-Feb-83 ISI-VAXA.ARPA.
841 FIPS PUB 98 Jan 83 Specification for Message Format for
Computer Based Message Systems
This RFC is FIPS 98. The purpose of distributing this document as an RFC is to make it easily accessible to the ARPA research community.
This RFC does not specify a standard for the ARPA Internet.
Obsoletes RFC 806.
840 Postel Apr 83 Official Protocols
This RFC has been revised, see RFC 880.
839 Smallberg Jan 83 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 31-Dec-82. The tests were run on
25-Jan-83.
Postel & Westine [page 11]
838 Smallberg Jan 83 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 31-Dec-82. The tests were run on
18-Jan-83.
837 Smallberg Jan 83 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 31-Dec-82. The tests were run on
11-Jan-83.
836 Smallberg Jan 83 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 20-Dec-82. The tests were run on 4-Jan-83 through 5-Jan-83.
835 Smallberg Dec 82 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 2-Dec-82. The tests were run on 28-Dec-82 through 5-Jan-83.
834 Smallberg Dec 82 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 2-Dec-82. The tests were run on 22-Dec-82. 833 Smallberg Dec 82 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 2-Dec-82. The tests were run on 14-Dec-82. 832 Smallberg Dec 82 Who Talks TCP?
This RFC is a survey of hosts to identify the implementation status
of Telnet, FTP, and Mail on TCP. The list of hosts was taken from
the NIC hostname table of 2-Dec-82. The tests were run on 7-Dec-82. Postel & Westine [page 12]
831 Braden Dec 82 Backup Access to the European Side of
SATNET
The purpose of this RFC is to focus discussion on a particular
Internet problem: a backup path for software maintenance of the
European sector of the Internet, for use when SATNET is partitioned. We propose a mechanism, based upon the Source Routing option of IP,
to reach European Internet sites via the VAN Gateway and UCL. This
proposal is not intended as a standard at this time.
830 Zaw-Sing Su Oct 82 A Distributed System for Internet Name Service
This RFC proposes a distributed name service for DARPA Internet. Its purpose is to focus discussion on the subject. It is hoped that a
general consensus will emerge leading eventually to the adoption of
standards.
829 Cerf Oct 82 Packet Satellite Technology Reference
Sources
This RFC describes briefly the packet satellite technology developed by the Defense Advanced Research Projects Agency and several other
participating organizations in the U.K. and Norway and provides a
bibliography of relevant papers for researchers interested in
experimental and operational experience with this dynamic
satellite-sharing technique.
828 Owen Aug 82 Data Communications: IFIP’s
International "Network" of Experts
This RFC is distributed to inform the ARPA Internet community of the activities of the IFIP technical committee on Data Communications,
and to encourage participation in those activities.
827 Rosen Oct 82 Exterior Gateway Protocol (EGP)
This RFC is proposed to establish a standard for Gateway to Gateway
procedures that allow the Gateways to be mutually suspicious. This
document is a DRAFT for that standard. Your comments are strongly
encouraged.
826 Plummer Nov 82 An Ethernet Address Resolution Protocol The purpose of this RFC is to present a method of Converting Protocol Addresses (e.g., IP addresses) to Local Network Addresses (e.g.,
Ethernet addresses). This is an issue of general concern in the ARPA Internet Community at this time. The method proposed here is
presented for your consideration and comment. This is not the
specification of an Internet Standard.
Postel & Westine [page 13]
825 Postel Nov 82 Request for Comments on Requests for
Comments
This RFC is intended to clarify the status of RFCs and to provide
some guidance for the authors of RFCs in the future. It is in a
sense a specification for RFCs.
824 MacGregor Aug 82 The Cronus Virtual Local Network
The purpose of this note is to describe the CRONUS Virtual Local
Network, especially the addressing related features. These features include a method for mapping between Internet Addresses and Local
Network addresses. This is a topic of current concern in the ARPA
Internet community. This note is intended to stimulate discussion.
This is not a specification of an Internet Standard.
823 Hinden Sep 82 The DARPA Internet Gateway
This RFC is a status report on the Internet Gateway developed by BBN. It describes the Internet Gateway as of September 1982. This memo
presents detailed descriptions of message formats and gateway
procedures, however, this is not an implementation specification, and such details are subject to change.
822 Crocker Aug 82 Standard for the Format of ARPA
Internet Text Messages
This document revises the specifications in RFC 733, in order to
serve the needs of the larger and more complex ARPA Internet. Some
of RFC 733’s features failed to gain adequate acceptance. In order
to simplify the standard and the software that follows it, these
features have been removed. A different addressing scheme is used,
to handle the case of internetwork mail; and the concept of
re-transmission has been introduced. Obsoletes RFC 733, NIC 41952. 821 Postel Aug 82 Simple Mail Transfer Protocol
The objective of Simple Mail Transfer Protocol (SMTP) is to transfer mail reliably and efficiently. SMTP is independent of the particular transmission subsystem and requires only a reliable ordered data
stream channel. Obsoletes RFC 788, 780, and 772.
820 Postel Jan 82 Assigned Numbers
This RFC is an old version, see RFC 870.
Postel & Westine [page 14]
819 Zaw-Sing Su Aug 82 The Domain Naming Convention for
Internet User Applications
This RFC is an attempt to clarify the generalization of the Domain
Naming Convention, the Internet Naming Convention, and to explore the implications of its adoption for Internet name service and user
applications.
818 Postel Nov 82 The Remote User Telnet Service
This RFC is the specification of an application protocol. Any host
that implements this application level service must follow this
protocol.
817 Clark Jul 82 Modularity and Efficiency in Protocol
Implementation
This RFC will discuss some of the commonly encountered reasons why
protocol implementations seem to run slowly.
816 Clark Jul 82 Fault Isolation and Recovery
This RFC describes the portion of fault isolation and recovery which is the responsibility of the host.
815 Clark Jul 82 IP Datagram Reassembly Algorithms
This RFC describes an alternate approach of dealing with reassembly
which reduces the bookkeeping problem to a minimum, and requires only one buffer for storage equal in size to the final datagram being
reassembled, which can reassemble a datagram from any number of
fragments arriving in any order with any possible pattern of overlap and duplication, and which is appropriate for almost any sort of
operating system.
814 Clark Jul 82 Name, Addresses, Ports, and Routes
This RFC gives suggestions and guidance for the design of the tables and algorithms necessary to keep track of these various sorts of
identifiers inside a host implementation of TCP/IP.
813 Clark Jul 82 Window and Acknowledgement Strategy in TCP
This RFC describes implementation strategies to deal with two
mechanisms in TCP, the window and the acknowledgement. It also
presents a particular set of algorithms which have received testing
in the field, and which appear to work properly with each other.
With more experience, these algorithms may become part of the formal specification, until such time their use is recommended.
Postel & Westine [page 15]
812 Harrenstien Mar 82 NICNAME/WHOIS
This RFC gives a description of what the NICNAME/WHOIS Server is and how to access it. This server together with the corresponding
Identification Data Base provides online directory look-up equivalent to the ARPANET Directory.
811 Harrenstien Mar 82 Hostnames Server
This RFC gives a description of what the Hostnames Server is and how to access it. The function of this particular server is to deliver
machine-readable name/address information describing networks,
gateways, hosts, and eventually domains, within the internet
environment.
810 Feinler Mar 82 DoD Internet Host Table Specification
This RFC specifies a new host table format applicable to both ARPANET and Internet needs. In addition to host name to host address
translation and selected protocol information, we have also included network and gateway name to address correspondence, and host
operating system information. This RFC obsoletes the host table
described in RFC 608.
809 Chang Feb 82 UCL Facsimile System
This RFC describes the features of the computerised facsimile system developed in the Department of Computer Science at UCL. First its
functions are considered and the related experimental work are
reported. Then the disciplines for system design are discussed.
Finally, the implementation of the system are described, while
detailed description are given as appendices.
808 Postel Mar 82 Summary of Computer Mail Services
Meeting Held at BBN on 10 January 1979 This RFC is a very belated attempt to document a meeting that was
held three years earlier to discuss the state of computer mail in the ARPA community and to reach some conclusions to guide the further
development of computer mail systems such that a coherent total mail service would continue to be provided.
807 Postel Feb 82 Multimedia Mail Meeting Notes
This RFC consists of notes from a meeting held at USC Information
Sciences Institute on the 12th of January to discuss common interests in multimedia computer mail issues and to agree on some specific
initial experiments.
Postel & Westine [page 16]
806 NBS Sep 81 Specification for Message Format for
Computer Based Message Systems
This RFC deals with Computer Based Message systems which provides a
basis for interaction between different CBMS by defining the format
of messages passed between them. This RFC is replaced by RFC 841. 805 Postel Feb 82 Computer Mail Meeting Notes
This RFC consists of notes from a meeting that was held at USC
Information Sciences Institute on 11 January 1982, to discuss
addressing issues in computer mail. The major conclusion reached at
the meeting is to extend the "username@hostname" mailbox format to
"username@host.domain", where the domain itself can be further
strutured.
804 CCITT Jan 82 CCITT Draft Recommendation T.4
This is the CCITT standard for group 3 facsimile encoding. This is
useful for data compression of bit map data.
803 Agarwal Nov 81 Dacom 450/500 Facsimile Data
Transcoding
The first part of this RFC describes in detail the Dacom 450 data
compression algorithms and is an update and correction to an earlier memorandum. The second part of this RFC describes briefly the Dacom 500 data compression algorithm as used by the INTELPOST
electronic-mail network under development by the US Postal Service
and several foreign administrators.
802 Malis Nov 81 The ARPANET 1822L Host Access Protocol This document proposed two major changes to the current ARPANET host access protocol. The first change will allow hosts to use logical
addressing (i.e., host addresses that are independent of their
physical location on the ARPANET) to communicate with each other, and the second will allow a host to shorten the amount of time that it
may be blocked by its IMP after it presents a message to the network (currently, the IMP can block further input from a host for up to 15 seconds). See RFCs 852 and 851.
801 Postel Nov 81 NCP/TCP Transition Plan
This RFC discusses the conversion of hosts from NCP to TCP. And
making available the principle services: Telnet, File Transfer, and Mail. These protocols allow all hosts in the ARPA community to share a common interprocess communication environment.
Postel & Westine [page 17]
800 Postel Nov 82 Requests for Comments Summary
This RFC is a slightly annotated list of the 100 RFCs from RFC 700
through RFC 799. This is a status report on these RFCs.
Postel & Westine [page 18]
初中英语介词用法总结 介词(preposition)：也叫前置词。在英语里，它的搭配能力最强。但不能单独做句子成分需要和名词或代词（或相当于名词的其他词类、短语及从句）构成介词短语，才能在句中充当成分。 介词是一种虚词，不能独立充当句子成分，需与动词、形容词和名词搭配，才能在句子中充当成分。介词是用于名词或代词之前，表示词与词之间关系的词类，介词常与动词、形容词和名词搭配表示不同意义。介词短语中介词后接名词、代词或可以替代名词的词（如：动名词v-ing）.介词后的代词永远为宾格形式。介词的种类： （1）简单介词：about, across, after, against, among, around, at, before, behind, below, beside, but, by, down, during, for, from, in, of, on, over, near, round, since, to, under, up, with等等。 （2）合成介词：inside, into, outside, throughout, upon, without, within （3）短语介词：according to, along with, apart from, because of, in front of, in spite of, instead of, owing to, up to, with reguard to （4）分词介词：considering, reguarding, including, concerning 介词短语：构成 介词+名词We go to school from Monday to Saturday. 介词+代词Could you look for it instead of me? 介词+动名词He insisted on staying home. 介词+连接代/副词I was thinking of how we could get there. 介词+不定式/从句He gives us some advice on how to finish it. 介词的用法： 一、介词to的常见用法 1.动词+to a)动词+ to adjust to适应, attend to处理；照料, agree to赞同,
超全的英语介词用法归纳总结常用介词基本用法辨析 表示方位的介词：in, to, on 1. in 表示在某地范围之内。 Shanghai is/lies in the east of China. 上海在中国的东部。 2. to 表示在某地范围之外。 Japan is/lies to the east of China. 日本位于中国的东面。 3. on 表示与某地相邻或接壤。 Mongolia is/lies on the north of China. 蒙古国位于中国北边。 表示计量的介词：at, for, by 1. at 表示“以……速度”“以……价格”。 It flies at about 900 kilometers an hour. 它以每小时900公里的速度飞行。 I sold my car at a high price. 我以高价出售了我的汽车。 2. for 表示“用……交换，以……为代价”。 He sold his car for 500 dollars. 他以五百元把车卖了。 注意：at表示单价(price) ，for表示总钱数。
3. by 表示“以……计”，后跟度量单位。 They paid him by the month. 他们按月给他计酬。 Here eggs are sold by weight. 在这里鸡蛋是按重量卖的。 表示材料的介词：of, from, in 1. of 成品仍可看出原料。 This box is made of paper. 这个盒子是纸做的。 2. from 成品已看不出原料。 Wine is made from grapes. 葡萄酒是葡萄酿成的。 3. in 表示用某种材料或语言。 Please fill in the form in pencil first. 请先用铅笔填写这个表格。They talk in English. 他们用英语交谈。 表示工具或手段的介词：by, with, on 1. by 用某种方式，多用于交通。 I went there by bus. 我坐公共汽车去那儿。 2. with表示“用某种工具”。 He broke the window with a stone. 他用石头把玻璃砸坏了。注意：with表示用某种工具时，必须用冠词或物主代词。
for语句可以在命令行提示符中使用，也可以在批处理文件中使用。这两种情况下唯一的区别是%和%%，参加下文说明。 一、for语句的格式： for [参数] 变量in (集合) do 命令[命令的参数] 二、for语句的作用：对集合内的元素逐一执行后面的命令。 1、如：for %%i in (你好) do echo %%i 将在屏幕上显示“你好”2个字。这里集合是“你好”，执行的命令是“echo”。由于集合中只有1个元素，因此循环只运行一次。 如果改成for %%i in (你好朋友) do echo %%i 将会显示2行文字，第一行为“你好”，第二行为“朋友”。因为2个词之间有空格，因此集合中就有了2个元素，循环将运行2次。 2、注意：以上for语句的运行方式是新建一个批处理文件，即扩展名为“.bat”的文件，内容为上面的命令，然后运行。为了批处理执行完不退出，可在最后加上一条pause>null命令，这样能看到执行的结果。要想通过cmd命令行执行的话，必须将%%换成%，即去掉一个%，如下： for %i in (你好) do echo %i 3、以下所有例子都是这样，若要在命令行提示符下执行，请将所有的%%改成一个%。 三、for语句详细说明： 上面语句格式中有的加了中括号[]，表示这个语句元素不是必须的，只在需要时使用。像刚才显示“你好”的命令中就没有使用[参数]这
个语句元素。所有语句元素间用空格隔开。 各语句元素的写法：for、in、do这3个符号是固定不变的 1、[参数]的种类：只有4种，分别是/d、/r、/l、/f（即目录Directory、递归recursion、序列list、文件file），他们用于对后面的集合的含义做出解释，请与下面的集合解释结合来看。这4个参数不区分大小写，可以联合使用，即一条for语句可以出现多个参数。 2、变量：除10个数字外（0－9）的所有符号（因为0－9往往作为形参使用，为了与此区别），变量名一般用单个字母表示即可，而且变量名区分大小写，即A和a是两个不同的变量。变量名前面必须是%，当在命令提示符下执行时，只用一个%；而在批处理程序中，必须用%%。 一行语句中，一般只需定义一个变量。使用/f参数中的tokens 选项可以将集合中的元素分解成多个值，并自动定义新的变量对应这些值。这时语句中可以使用多个变量，通常按字母顺序命名，即第一个是%%a，那么后一个就用%%b。如果第一个是%%i，后一个就用%%j。依此类推。具体看后面的相关内容。 变量可以直接在do后面的命令中使用。每次使用的变量总数不超过52个。 3、集合：集合必须放在括号里。集合是一行文本，这行文本可能有几种类型，如“你好”只是一串字符；“c:\boot.ini”是一个文件；“dir /b”是一个命令。 （1）如果for语句中没有使用任何参数，对待集合文本的处理方式是：
介词for用法归纳 用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做？ That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了？ He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的。如： 他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么？ We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗？ Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者。如： She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth＝为卖出某物而打广告；advertise for sth＝为寻找某物而打广告。如：advertise for a job=登广告求职。由于受汉语“为”的影响，而此处误加了介词for。类似地，汉语中的“为人民服务”，说成英语是serve the people，而不是serve for the people，“为某人的死报仇”，说成英语是avenge sb’s death，而不是avenge for sb’s death，等等。用法3：(表用途)用于，用来。如： Knives are used for cutting things. 小刀是用来切东西的。 This knife is for cutting bread. 这把小刀是用于切面包的。 It’s a machine for slicing bread. 这是切面包的机器。 The doctor gave her some medicine for her cold. 医生给了她一些感冒药。 用法4：为得到，为拿到，为取得。如： He went home for his book. 他回家拿书。 He went to his friend for advice. 他去向朋友请教。 She often asked her parents for money. 她经常向父母要钱。
【备战高考】英语介词用法总结(完整) 一、单项选择介词 1． passion, people won't have the motivation or the joy necessary for creative thinking. A．For . B．Without C．Beneath D．By 【答案】B 【解析】 【详解】 考查介词辨析。句意：没有激情，人们就不会有创新思维所必须的动机和快乐。A. For 对于；B. Without没有； C. Beneath在……下面 ; D. By通过。没有激情，人们就不会有创新思维所必须的动机和快乐。所以空处填介词without。故填without。 2．Modern zoos should shoulder more social responsibility _______ social progress and awareness of the public. A．in light of B．in favor of C．in honor of D．in praise of 【答案】A 【解析】 【分析】 【详解】 考查介词短语。句意：现代的动物园应该根据社会的进步和公众的意识来承担更多的社会责任。A. in light of根据，鉴于；B. in favor of有利于，支持；C. in honor of 为了纪念；D. in praise of歌颂，为赞扬。此处表示根据，故选A。 3．If we surround ourselves with people _____our major purpose, we can get their support and encouragement. A．in sympathy with B．in terms of C．in honour of D．in contrast with 【答案】A 【解析】 【详解】 考查介词短语辨析。句意：如果我们周围都是认同我们主要前进目标的人，我们就能得到他们的支持和鼓励。A. in sympathy with赞成；B. in terms of 依据；C. in honour of为纪念； D. in contrast with与…形成对比。由“we can get their support and encouragement”可知，in sym pathy with“赞成”符合句意。故选A项。 4．Elizabeth has already achieved success_____her wildest dreams. A．at B．beyond C．within D．upon
英语介词for的用法归纳总结用法1：(介词for表目的)为了 They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做? That s what we re here for. 这正是我们来的目的。 What s she gone for this time? 她这次去干什么去了? He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的 他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的 He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(介词for表利益)为，为了 What can I do for you? 你想要我什么? We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗?
Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者 She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth=为卖出某物而打广告;advertise for sth=为寻找某物而打广告advertise for a job=登广告求职。由于受汉语为的影响，而此处误加了介词for。类似地，汉语中的为人民服务，说成英语是serve the people，而不是serve for the people，为某人的死报仇，说成英语是avenge sb s death，而不是avenge for sb s death，等等。 用法3：(介词for表用途)用于，用来 Knives are used for cutting things. 小刀是用来切东西的。
用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做? That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了? He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的。如：他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么? We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗? Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者。如：
批处理命令for语句的基本用法 [系列教程]批处理for语句从入门到精通[20101225更新] ____________________________版主提醒 ____________________________ 文档来自于网络搜索 为了避免影响技术讨论、提高看帖的舒适性，请大家不要在此帖下跟 无实质内容的口水帖，特别是纯顶、纯支持、纯感谢、路过之类的帖子， 管理人员将不定期清理此类回帖，请大家多参与讨论少灌水，与人方便， 终将给自己带来方便，谢谢合作。 ________________________________________________________________ 文档来自于网络搜索 批处理是一门简单的脚本语言，虽然不能独当一面，但是，若作为工作中的辅助工具，绝对会让大家有随用随写、称心如意的畅快感。 文档来自于网络搜索 和其他语言相比，批处理语言有其先天性的优势： 1、系统自带，无需另行安装； 2、命令少，语句简洁，上手非常快； 3、编写出来的脚本小巧玲珑，随写随用； 但是，因为它以命令行方式工作，操作多有不便，在图形界面大行其道的windows世界里，多多少少会让大众望而却步；就算是对命令行有好感的新手，面对微软有如天书的帮助文件，很多人也会败下阵来，因此，论坛里很多会员也发出了编写系统的批处理教程的呼声。
文档来自于网络搜索 编写系统的批处理新手教程，一直是论坛管理层讨论的热点问题，但是，各位管理人员大多都有工作在身，而系统的教程涉及的面是如此之广，面对如此浩大的工程，仅凭一两个人的力量，是难以做好的，因此，本人退而求其次，此次发布的教程，以专题的形式编写，日后人手渐多之后，再考虑组织人力编写全面的教程。 文档来自于网络搜索之所以选择最难的for，一是觉得for最为强大，是大多数人最希望掌握的；二是若写其他命令教程，如果没有for的基础，展开来讲解会无从下手；三是for也是批处理中最复杂最难掌握的语句，把它攻克了，批处理的学习将会一片坦途。 文档来自于网络搜索 这次的for语句系列教程，打算按照for语句的5种句式逐一展开，在讲解for/f的时候，会穿插讲解批处理中一个最为关键、也是新手最容易犯错的概念：变量延迟，大纲如下： 文档来自于网络搜索一前言 二for语句的基本用法 三for /f（含变量延迟） 四for /r 五for /d 六for /l 遵照yibantiaokuan的建议，在顶楼放出此教程的txt版本、word版本和pdf版本，以方便那些离线浏览的会员。 文档来自于网络搜索[本帖最后由namejm于2010-12-26 02:36编辑]
for的用法完全归纳 用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做？ That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了？ He was waiting for the bus. 他在等公共汽车。 在通常情况下，英语不用for doing sth 来表示目的。如：他去那儿看他叔叔。 误：He went there for seeing his uncle.正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么？ We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗？ Do more exercise for the good of your health. 为了健康你要多运动。 (1)有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通 常用for 来引出间接宾语，表示间接宾语为受益者。如： She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth＝为卖出某物而打广告；advertise for sth＝为寻找某物而打广告。如：advertise for a job=登广告求职。由于受汉语“为”的影响，而此处误加了介词for。类似地，汉语中的“为人民服务”，说成英语是serve the people，而不是serve for the people，“为某人的死报仇”，说成英语是avenge sb’s death，而不是avenge for sb’s death，等等。 用法3：(表用途)用于，用来。如： Knives are used for cutting things. 小刀是用来切东西的。 This knife is for cutting bread. 这把小刀是用于切面包的。 It’s a machine for slicing bread. 这是切面包的机器。 The doctor gave her some medicine for her cold. 医生给了她一些感冒药。 用法4：为得到，为拿到，为取得。如： He went home for his book. 他回家拿书。 He went to his friend for advice. 他去向朋友请教。 She often asked her parents for money. 她经常向父母要钱。 We all hope for success. 我们都盼望成功。 Are you coming in for some tea? 你要不要进来喝点茶？ 用法5：给(某人)，供(某人)用。如： That’s for you. 这是给你的。 Here is a letter for you. 这是你的信。 Have you room for me there? 你那边能给我腾出点地方吗？ 用法6：(表原因、理由)因为，由于。如：
批处理命令格式.txt人永远不知道谁哪次不经意的跟你说了再见之后就真的再也不见了。一分钟有多长？这要看你是蹲在厕所里面，还是等在厕所外面……echo 表示显示此命令后的字符 echo off 表示在此语句后所有运行的命令都不显示命令行本身 @与echo off相象，但它是加在每个命令行的最前面，表示运行时不显示这一行的命令行（只能影响当前行）。 call 调用另一个批处理文件（如果不用call而直接调用别的批处理文件，那么执行完那个批处理文件后将无法返回当前文件并执行当前文件的后续命令）。 pause 运行此句会暂停批处理的执行并在屏幕上显示Press any key to continue...的提示，等待用户按任意键后继续 rem 表示此命令后的字符为解释行（注释），不执行，只是给自己今后参考用的（相当于程序中的注释）。 例1：用edit编辑a.bat文件，输入下列内容后存盘为c: a.bat，执行该批处理文件后可实现：将根目录中所有文件写入 a.txt中，启动UCDOS，进入WPS等功能。 批处理文件的内容为: 命令注释： @echo off 不显示后续命令行及当前命令行 dir c: *.* >a.txt 将c盘文件列表写入a.txt call c: ucdos ucdos.bat 调用ucdos echo 你好显示"你好" pause 暂停,等待按键继续 rem 准备运行wps 注释：准备运行wps cd ucdos 进入ucdos目录 wps 运行wps 批处理文件的参数 批处理文件还可以像C语言的函数一样使用参数（相当于DOS命令的命令行参数），这需要用到一个参数表示符“%”。 %[1-9]表示参数，参数是指在运行批处理文件时在文件名后加的以空格（或者Tab）分隔的字符串。变量可以从%0到%9，%0表示批处理命令本身，其它参数字符串用%1到%9顺序表示。例2：C:根目录下有一批处理文件名为f.bat，内容为： @echo off format %1 如果执行C: >f a: 那么在执行f.bat时，%1就表示a:，这样format %1就相当于format a:，于是上面的命令运行时实际执行的是format a: 例3：C:根目录下一批处理文件名为t.bat，内容为: @echo off type %1 type %2 那么运行C: >t a.txt b.txt %1 : 表示a.txt %2 : 表示b.txt 于是上面的命令将顺序地显示a.txt和b.txt文件的内容。 特殊命令 if goto choice for是批处理文件中比较高级的命令，如果这几个你用得很熟练，你就是批
介词for 的常见用法归纳 贵州省黔东南州黎平县黎平一中英语组廖钟雁介词for 用法灵活并且搭配能力很强，是一个使用频率非常高的词，也是 高考必考的重要词汇，现将其常见用法归纳如下，供参考。 1.表时间、距离或数量等。 ①意为“在特定时间，定于，安排在约定时间”。如： The meeting is arranged for 9 o’clock. 会议安排在九点进行。 ②意为“持续达”，常于last、stay 、wait等持续性动词连用，表动作持续的时间，有时可以省略。如： He stayed for a long time. 他逗留了很久。 The meeting lasted （for）three hours. 会议持续了三小时。 ③意为“（距离或数量）计、达”。例如： He walked for two miles. 他走了两英里。 The shop sent me a bill for $100.商店给我送来了100美元的账单。 2. 表方向。意为“向、朝、开往、前往”。常与head、leave 、set off、start 等动词连用。如： Tomorrow Tom will leave for Beijing. 明天汤姆要去北京。 He put on his coat and headed for the door他穿上大衣向门口走去。 介词to也可表示方向，但往往与come、drive 、fly、get、go、lead、march、move、return、ride、travel、walk等动词连用。 3.表示理由或原因,意为“因为、由于”。常与thank、famous、reason 、sake 等词连用。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 For several reasons, I’d rather not meet him. 由于种种原因，我宁可不见他。 The West Lake is famous for its beautiful scenery.西湖因美景而闻名。 4.表示目的,意为“为了、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 He plays the piano for pleasure. 他弹钢琴是为了消遣。 There is no need for anyone to know. 没必要让任何人知道。 5.表示动作的对象或接受者,意为“给、为、对于”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 Here is a letter for you. 这儿有你的一封信。
介词的用法 1.表示地点位置的介词 1)at ,in, on, to，for at (1)表示在小地方; (2)表示“在……附近，旁边” in (1)表示在大地方; (2)表示“在…范围之内”。 on 表示毗邻，接壤，“在……上面”。 to 表示在……范围外，不强调是否接壤；或“到……” 2)above, over, on 在……上 above 指在……上方,不强调是否垂直，与below相对； over指垂直的上方,与under相对,但over与物体有一定的空间，不直接接触。 on表示某物体上面并与之接触。 The bird is flying above my head. There is a bridge over the river. He put his watch on the desk. 3)below, under 在……下面 under表示在…正下方 below表示在……下，不一定在正下方 There is a cat under the table. Please write your name below the line. 4)in front [frant]of, in the front of在……前面 in front of…意思是“在……前面”，指甲物在乙物之前，两者互不包括；其反义词是behind（在……的后面）。There are some flowers in front of the house.(房子前面有些花卉。) in the front of 意思是“在…..的前部”，即甲物在乙物的内部.反义词是at the back of…（在……范围内的后部）。 There is a blackboard in the front of our classroom. 我们的教室前边有一块黑板。 Our teacher stands in the front of the classroom. 我们的老师站在教室前.(老师在教室里) 5）beside，behind beside 表示在……旁边 behind 表示在……后面 2.表示时间的介词 1)in , on，at 在……时 in表示较长时间，如世纪、朝代、时代、年、季节、月及一般（非特指）的早、中、晚等。 如in the 20th century, in the 1950s, in 1989, in summer, in January, in the morning, in one’s life , in one’s thirties等。 on表示具体某一天及其早、中、晚。 如on May 1st, on Monday, on New Year’s Day, on a cold night in January, on a fine morning, on Sunday afternoon等。 at表示某一时刻或较短暂的时间，或泛指圣诞节，复活节等。 如at 3:20, at this time of year, at the beginning of, at the end of …, at the age of …, at Christmas，at night, at noon, at this moment等。 注意：在last, next, this, that, some, every 等词之前一律不用介词。如：We meet every day. 2)in, after 在……之后 “in +段时间”表示将来的一段时间以后； “after+段时间”表示过去的一段时间以后； “after+将来的时间点”表示将来的某一时刻以后。 3)from, since 自从…… from仅说明什么时候开始，不说明某动作或情况持续多久；
批处理文件基础知识 一、单符号message指定让MS-DOS在屏幕上显示的正文 ~ ①在for中表示使用增强的变量扩展。 ②在%var:~n,m%中表示使用扩展环境变量指定位置的字符串。 ③在set/a中表示一元运算符，将操作数按位取反。 ! ①在set /a中一元运算符，表示逻辑非。比如set /a a=!0，这时a就表示逻辑1。 @ ①隐藏命令行本身的回显，常用于批处理中。 % ①在set /a中的二元运算符，表示算术取余。 ②命令行环境下，在for命令in前，后面接一个字符（可以是字母、数字或者一些特定字符），表示指定一个循环或者遍历指标变量。 ③批处理中，后接一个数字表示引用本批处理当前执行时的指定的参数。 ④其它情况下，%将会被脱去（批处理）或保留（命令行） ^ ①取消特定字符的转义作用，比如& | > < ! "等，但不包括%。比如要在屏幕显示一些特殊的字符，比如> >> | ^ &等符号时，就可以在其前面加一个^符号来显示这个^后面的字符了，^^就是显示一个^，^|就是显示一个|字符了; ②在set/a中的二元运算符，表示按位异或。 ③在findstr/r的[]中表示不匹配指定的字符集。 & ①命令连接字符。比如我要在一行文本上同时执行两个命令，就可以用&命令连接这两个命令。 ②在set/a中是按位与。 : ①标签定位符，表示其后的字符串为以标签，可以作为goto命令的作用对象。比如在批处理文件里面定义了一个":begin"标签，用"goto begin"命令就可以转到":begin"标签后面来执行批处理命令了。 ②在%var:string1=string2%中分隔变量名和被替换字串关系。 | ①管道符，就是将上一个命令的输出，作为下一个命令的输入."dir /a/b |more"就可以逐屏的显示dir命令所输出的信息。 ②在set/a中的二元运算符，表示按位或。 ③在帮助文档中表示其前后两个开关、选项或参数是二选一的。 / ①表示其后的字符（串）是命令的功能开关（选项）。比如"dir /s/b/a-d"表示"dir"命令指定的不同的参数。 ②在set/a中表示除法。 > ①命令重定向符，将其前面的命令的输出结果重新定向到其后面的设备中去，后面的设备中的内容被覆盖。比如可以用"dir > lxmxn.txt"将"dir"命令的结果输出到"lxmxn.txt"这个文本文件中去。 ②在findstr/r中表示匹配单词的右边界，需要配合转义字符\使用。 < ①将其后面的文件的内容作为其前面命令的输入。 ②在findstr/r中表示匹配单词的左边界，需要配合转义字符\使用。 . ①在路径的\后紧跟或者单独出现时：
介词的归纳 一、单项选择介词 1．（重庆）Last year was the warmest year on record, with global temperature 0.68 ℃ ________ the average. A．below B．on C．at D．above 【答案】D 【解析】 【详解】 考查介词。句意：去年是有纪录以来最热的一年，全球平均气温上升0.68度。A. below低于；B. on在……之上；C. at在；D. above超过，多于。根据前一句Last year was the warmest year on record推知，温度应该是上升了，故用介词above。 【点睛】 with的复合结构中，复合宾语中第一部分宾语由名词和代词充当，第二部分补足语由形容词，副词，介词短语，动词不定式或分词充当。而本题考查with +名词/代词+介词短语,而介词的使用则根据当时语境的提示来做出相应的变化即句中的the warmest year on record 起重要作用，可知高出平均气温。 2．According to Baidu, the high-quality content of Cloud Music will reach massive users _______ Baidu’s app and video platform. A．in honor of B．in view of C．by virtue of D．by way of 【答案】C 【解析】 【详解】 考查介词短语。句意：根据百度的说法，云音乐的高质量内容将借助于百度应用和视频平台到达广大用户。A. in honor of向……致敬；B. in view of考虑到；C. by virtue of借助于；D. by way of通过。根据句意可知，此处要表达“借助于”。故选C项。 3．We charge parcels ________ weight, rather than individual units. A．in honor of B．in contact with C．in terms of D．in connection with 【答案】C 【解析】 【详解】 考查介词短语。句意：我们根据包裹的重量，而不是包裹的件数收费。A. in honor of为了对……表示敬意；B. in contact with与……有联系，接触；C. in terms of根据，在……方面；D. in connection with与……有关，有联系。表示根据什么计费。故选C。 【点睛】
介词（preposition） 又称前置词，是一种虚词。介词不能单独做句子成分。介词后须接宾语，介词与其宾语构成介词短语。 一、介词从其构成来看可以分为： 1、简单介词（Simple prepositions）如：at ,by, for, in, from, since, through等； 2、复合介词（Compound prepositions）如：onto, out of, without, towards等； 3、短语介词（phrasal prepositions）如；because of, instead of, on account of, in spite of, in front of等； 4、二重介词（double prepositions）如：from behind, from under, till after等； 5、分词介词（participial prepositions），又可称动词介词（verbal prepositions）如：during, concerning, excepting, considering, past等。 二、常见介词的基本用法 1、 about 关于 Do you know something about Tom？ What about this coat？（……怎么样） 2、 after 在……之后 I’m going to see you after supper. Tom looked after his sick mother yesterday.（照看） 3、 across 横过 Can you swim across the river. 4、 against 反对 Are you for or against me? Nothing could make me turn against my country.（背叛） 5、 along 沿着 We walked along the river bank. 6、 before 在……之前 I hope to get there before seven o’clock. It looks as though it will snow before long.（不久） 7、behind 在……后面 The sun is hidden behind the clouds. 8、by 到……时 We had learned ten English songs by the end of last term. 9、during 在……期间 Where are you going during the holiday. 10、except 除了 Everyone except you answered the question correctly. 11、for 为了 The students are studying hard for the people. 12、from 从 I come from Shanghai. 13、in 在……里 on 在……上面 under在……下面 There are two balls in/on/under the desk. 14、near 在……附近 We live near the park. 15、of ……的 Do you know the name of the winner. 16、over 在……正上方 There is a bridge over the river. Tom goes over his English every day.（复习） 17、round/around 围绕 The students stand around the teacher. 18、to 朝……方向 Can you tell me the way to the cinema. 19、towards朝着 The car is traveling towards Beijing.