分享
 
 
 

RFC122 - Network specifications for UCSBs Simple-Minded File System

王朝other·作者佚名  2008-05-31
窄屏简体版  字體: |||超大  

Network Working Group James E. White

Request for Comments: 122 UC Santa Barbara

NIC 5834 26 April 1971

NETWORK SPECIFICATIONS FOR UCSB's

SIMPLE-MINDED FILE SYSTEM

CONTENTS

Page

I. Preface........................................ 3

II. Implementation................................. 3

III. Login.......................................... 3

IV. Service Offered................................ 4

V. Primitive File Operations...................... 6

V.A. Allocate File (ALF)...................... 6

V.B. Update File (UDF)........................ 7

V.C. Replace File (RDF)....................... 8

V.D. Retrieve File (RTF)...................... 9

V.E. Space File (SPF)......................... 9

V.F. Delete File (DLF)........................ 10

V.G. Rename File (RNF)........................ 10

V.H. File No Operation (FNO).................. 10

V.I. No Operation (NOP)....................... 11

VI. Input Stream Format............................ 11

VII. Output Stream Format........................... 16

FIGURES

Page

Figure 1. Filename/PassWord Character Sets........... 5

Figure 2. Command Op Codes........................... 12

Figure 3. Defined Command Fields..................... 13

Figure 4. Definition of Command FLAGS Bits........... 14

Figure 5. Defined Command Response Fields............ 18

Figure 6. Completion Codes........................... 19

I. Preface

UCSB will provide file storage for Network users. UCSB's Simple

Minded File System (SMFS) is addressed as socket number X'401', site

3. No accounting parameters are required. This document is intended

to provide programmers with the information necessary to communicate

with SMFS which conducts all Network transactions trough its NCP

which operates under the Host-Host protocol of August 3, 1970.*

II. Implementation

The following information is not essential to use of SMFS but may be

of interest. SMFS will store user's files on IBM 2316 disk packs,

each with 29M 8-bit bytes of storage capacity. UCSB has two 2314

units, each with eight drives on-line. Initially, one drive will be

allocated for Network storage, and the appropriate pack will always

be mounted an that drive, and hence Accessible to SMFS without

operator intervention. UCSB estimates that for the next year it will

have up to four drives that it can devote to Network use. The

second, third, and fourth drives will be allocated only as the need

arises. SMFS is written to accommodate any number of on-line drives

without modification.

If necessary, UCSB will investigate the possibility of making one of

the four drives a come-and-go drive on which one of a number of packs

can be mounted as required. Hence, the potential exists for

increased storage capacity with an accompanying increase in access

time.

Files stored with SMFS will be backed up to tape daily. The back-up

tape(s) will be off-line and available only in case the on-line

copies are destroyed.

In no sense does USB eXPect to become _the_ file storage node of the

Network; it hasn't the capacity. UCSB _is_ equipped, however, to

make a limited amount of secondary storage immediately available to

the Network community.

III. Login

SMFS can simultaneously service any number of Network users up to

some assembly-parameters maximum (currently ten). A potential user

must establish a pair of Network connections

*At the time of this writing, the NCP modifications of RFC#107 have not

as yet been implemented at UCSB.

(i.e., one full-duplex connection) to SMFS by executing a standard

ICP to socket X'401', site 3. SMFS always listens on that socket.

It will accept any call it receives -- say from the user's receive

socket 'm' -- and over the connection thus established transmit a

32-bit receive socket number (call it 'n'), and then close the

connection. SMFS will then issue two connection requests -- one

involving its receive socket 'n' and the user's send socket 'm+l', in

other involving its send socket 'n+l' and the user's receive socket

'm'. Once these two connections have been established, the user will

be considered logged in. A deviation from the Initial Connection

Protocol will occur only if SMFS or its NCP has insufficient

resources to support another connection.

SMFS will maintain its connections to the user indefinitely. It will

voluntarily terminate its connections to the user only if (1) a bad

op code is encountered in a user command (see Section VI), or (2)

closing one of the connections is required to signal end-of-data (see

Section V.D.). Barring such an occurrence, the user should close his

connections to SMFS when through, at which time SMFS will consider

the user logged out.

In the discussion to follow, the following terms are used. The

connections on which the user transmits data to and receives data

from SMFS are designated the input and output connections,

respectively (i.e., SMFS's rather than the user's point of view is

adopted). The string of bits which passes from the user to SMFS over

the input connection during the life of that connection is called the

_input stream_; the string of bits which passes from SMFS to the user

over the output connection during the life of that connection is

called the _output stream_.

IV. Service Offered

SMFS will provide storage for sequential, binary files of length

greater than or equal to an assembly-parameter minimum (currently one

bit) and less than or equal to an assembly-parameter maximum

(currently 25 million bits). There is no restriction on the contents

of the file.

Every file stored with SMFS has a _filename_, which may be any string

of from one to 36, 8-bit characters chosen from the set:

{ A,...,Z,0,...9,blank }

Graphic EBCDIC Code (Hex) ASCII Code (Hex)

UC LC UC LC UC LC

A a C1 81 41 61

B b C2 82 42 62

C c C3 83 43 63

D d C4 84 44 64

E e C5 85 45 65

F f C6 86 46 66

G g C7 87 47 67

H h C8 88 48 68

I i C9 89 49 69

J j D1 91 4A 6A

K k D2 92 4B 6B

L l D3 93 4C 6C

M m D4 94 4D 6D

N n D5 95 4E 6E

O o D6 96 4F 6F

P p D7 97 50 70

Q q D8 98 51 71

R r D9 99 52 72

S s E2 A2 53 73

T t E3 A3 54 74

U u E4 A4 55 75

V v E5 A5 56 76

W w E6 A6 57 77

X x E7 A7 58 78

Y y E8 A8 59 79

Z z E9 A9 5A 7A

0 - F0 - 30 -

1 - F1 - 31 -

2 - F2 - 32 -

3 - F3 - 33 -

4 - F4 - 34 -

5 - F5 - 35 -

6 - F6 - 36 -

7 - F7 - 37 -

8 - F8 - 38 -

9 - F9 - 39 -

blank - 40 - 20 -

Figure 1

Filename/Password Character Sets

Filenames may be specified by the user in either EBCDIC or ASCII (see

Figure 1), and the characters A,...,Z may be either upper- or lower-

case. However, the acceptance by SMFS of both upper- and lower-case,

and both EBCDIC and ASCII, is provided only as a convenience to the

user. In particular, such distinctions don't increase the number of

unique filenames that can be generated; the filenames 'FILE NUMBER 1'

and 'file number 1', in EBCDIC or ASCII, designate the same file.

Every file stored with SMFS may optionally be protected against

unauthorized retrieval and/or modification. When a file is created,

the user may associate with it a _modification password_ and/or an

_access password_. Thereafter, SMFS will demand that the appropriate

password be supplied before the file is modified or retrieved,

respectively. Since SMFS protects each file independently against

unauthorized modification and retrieval, a group of users can be

given access to a file while a single individual retains the

exclusive right to modify it. If no password is defined for a

particular type of reference to a file, then such references are

unrestricted. Passwords have the same attributes as filenames --

same length restrictions and same character sets.

Because of the manner in which SMFS writes files onto secondary

storage, it must insure that while one user is modifying a file, no

other user is simultaneously either modifying or retrieving the same

file. This requirement is effected by a mechanism internal to SMFS

and hence transparent to users, with the exception that when a user

attempts to retrieve or modify a file currently being modified by

another user, SMFS will delay action upon the request until the

current modification is complete. There is no restriction on the

number of users which may concurrently retrieve the same file.

V. Primitive File Operations

SMFS recognizes and will execute the following primitive file

operations:

V.A. Allocate File (ALF)

SMFS regards the reservation of filename, the assignment of

passwords, and the reservation of secondary storage as an operation

distinct from that of transmitting the file's contents. The

operation is called _file allocation_, abbreviated ALF. In

allocating a file, the user specifies the filename to be assigned to

it, the access password (if any), and the estimated size of the file

in bits. SMFS checks the proposed filename to insure that it doesn't

duplicate that of an existing file. SMFS also checks to insure that

it has sufficient secondary storage available to accommodate the new

file. If both requirements are met, SMFS allocates the file; the

filename is reserved, secondary storage is reserved, and the password

information is recorded.

In reserving secondary storage for a file, SMFS adds its estimate of

its overhead in storing the file to the user-declared size of the

file. In general, the user should slightly over-estimate the size of

his file at allocation. SMFS allocates a fixed amount of storage on

the basis of that estimate, an amount which cannot be increased

later. SMFS's actual overhead in storing a file is a function of the

manner in which the contents of the file are transmitted by the user.

The overhead is minimal when the file is transmitted in a single

series of operations (see Section VI) and increases as the number of

operations increases. It is the overhead associated with single-

series transmission that SMFS adds to the file size specified by the

user to determine the amount of storage to allocate. Hence, for

multiple-series transmission, the overhead will have been

underestimated.

V.B. Update File (UDF)

The operation of transmitting part or all of a previously allocated

file's contents for storage by SMFS is called _updating_ the _file_

(UDF). The user specifies the filename of the file to be updated,

the modification password if required, the amount of data in bits to

be added to the file, and finally the data itself. SMFS locates the

file on secondary storage, checks the password for validity, if

appropriate, and adds the data to the file. SMFS considers the

update complete when either the specified number of bits have been

extracted from the input stream and stored, or when the user

terminates transmission by closing the connection.

The data transmitted in a UDF operation is _concatenated_ to the

current contents of the file. Boundaries between updates are

transparent to the user when the file is retrieved. Hence, for

example, the contents of a file might be transmitted to SMFS in two

distinct UDF operations, and later retrieved in a single RTF

operation (see Section V.D.). The user should view a file stored

with SMFS as a potentially very long bit string which may be

transmitted to SMFS in any number of variable-length _segments_, and

is retrievable in any number of variable-length segments, with the

manner of segmentation chosen during retrieval independent of that

selected during the updating process.

The user may optionally request that SMFS 'remember' the manner in

which a file was updated, i.e., along with the data, store sufficient

information to reconstruct segment boundaries at retrieval time.

Such a file is said to be _formatted_. In retrieving a formatted

file, the user, rather than requesting that SMFS transmit the next

'n' bits of the file as he would do for an unformatted file (see

Section V.D.), requests that SMFS transmit the next segment of the

file; it is then SMFS's responsibility to supply the length of the

segment. Hence, the notion of a _logical record_ is introduced.

Of course, since the user may format the contents of a file in any

way he chooses, he can embed record-length information in the data

itself. Hence, the user can implement a record structure in a way

that's transparent to SMFS. This scheme, however, requires during

retrieval that, for each logical record retrieved, the user fetch

first the length field and then, using the length as an operand,

fetch the data itself. In this kind of arrangement, the retrieval

rate is apt to suffer. However, by allowing SMFS knowledge of

logical-record boundaries, the feedback loop is effectively shortened

(SMFS being closer to the file); hence, the potential exists for an

increased retrieval rate.

If the user intends that a file be formatted, he must so specify in

every update and every retrieve operation referencing that file.

SMFS in no way flags a file to indicate that it is formatted. Hence,

if the user invokes the option during retrieval without having done

so when the file was stored, results will be erroneous. Furthermore,

if an update of a formatted file is terminated before the bit count

for the operation is exhausted (i.e., because the user closed the

connection), retrieval results will again be erroneous.

V.C. Replace File (RPF)

The replace-file (RPF) operation is identical to UDF, except that the

new file segment, rather than being concatenated to the existing

file, _replaces_ the entire contents of the file. The previous

contents of the file are lost, and the new segment becomes the only

segment in the file.

RPF may be used to rewrite an existing file. If the rewritten file

is to contain just a single segment, that segment may be transmitted

to SMFS in an RPF operation. Otherwise, the first segment of the new

file must be transmitted in an RPF operation, and all succeeding

segments in UDF operations. Alternately, a dummy (bit count of zero)

RPF operation may be inserted before the first real segment is

transmitted; all segments of the file may then be transmitted in UDF

operations.

V.D. Retrieve File (RTF)

The operation which retrieves all or part of a file's contents is

called file retrieval (RTF). The user specifies the filename of the

file to be retrieved, the access password if required, and the amount

of data in bits to be fetched from the file. SMFS locates the file

on secondary storage, checks the password for validity (if

appropriate), and copies the bit count and the requested file segment

into the output stream. SMFS considers the retrieval complete when

either the requested number of bits have been placed in the output

stream, or when the contents of the file are exhausted. In this

latter case, SMFS closes the connection to signal end-of-data to the

user.

Successive RTF operations referencing the same file cause successive

segments of the file to be transmitted, provided that the operations

are juxtaposed in the input stream (however, NOP's may be

interspersed anywhere in the input stream). When a series of RTF

operations referencing a particular file is broken by an operation

referencing another file, or by a different type of operation

involving the same file, the next RTF operation designating the

original file will cause the _first_ segment of that file to be

transmitted. The manner in which the user segments a file for a

series of retrieve operations need bear no relationship to the

segmentation scheme employed when the file was updated, nor to that

employed in previous retrievals.

If the user elected to have his file formatted by SMFS, he should

re-invoke the option in the RTF operation, in which case SMFS will

supply the length of the segment, and place both it and the segment

itself into the output stream.

V.E. Space File (SPF)

Files stored with SMFS are sequential in organization. That is the

n+1th segment of the file cannot be retrieved without first

processing the nth segment. The user may, however, upon occasion,

wish to retrieve only selected segments of a file. This he could do,

effectively, by retrieving each segment of the file and flushing

those with which he was currently unconcerned. To avoid needless

Network traffic, SMFS provides a mechanism for flushing file segments

locally. The operation is called _spacing_ a file (SPF). It is

identical to RTF with the exception that transmission of data (but

not bit count) is suppressed. SPF operations may be freely inserted

anywhere within a series of RTF operations designating a particular

file, with the desired results.

V.F. Delete File (DLF)

A file may be deleted at any time after allocation. The user

specifies the filename of the file to be deleted and the modification

password if required. SMFS locates the file on secondary storage,

checks the password for validity (if appropriate), and, if the

password is correct, deletes the file. The filename is made

available for reassignment, and the secondary storage allocated to

the file is reclaimed by SMFS. The contents (if any) of the file are

lost.

V.G. Rename File (RNF)

A file stored with SMFS may be renamed at any time after allocation.

The user specifies the current filename of the file to be renamed,

the modification password if any, and the proposed new filename.

SMFS locates the file on secondary storage, checks the password for

validity (if appropriate), and assures that the proposed new filename

is not already assigned to another file. If these requirements are

met, the file is renamed, and all subsequent references to the file

must be by the newly-assigned filename.

RNF provides a means for protecting a file that must be rewritten in

its entirety against failures in the Net, or in the sending or

receiving host. The strategy is as follows. Allocate a new file,

assigning it some temporary name. Transmit the revised file contents

in one more UDF and/or RPF operations. Then delete the original file

and, using RNF, replace the newly-created file's temporary filename

with that of the original file.

V.H. File no Operation (FNO)

FNO is a dummy operation which is provided for use in terminating a

series of RTF operations. Should the user desire to retrieve the

contents of a file twice in succession, he may do so with a series of

RTF/SPF operations, followed by a FNO followed by a second series of

RTF/SPF operations. Each RTF/SPF operation in the first series will

retrieve/flush the next segment of the file. The first operation of

the second string, since it _is_ the first of a string, will, as

explained in Section V.D., retrieve/flush the _first_ segment of the

file. The remaining operations in the second string will, of course

retrieve/flush the 2nd, 3rd, etc., segments of the file. Hence, the

contents of the file are transmitted twice. FNO, when it terminates

such a string of operations, effectively repositions the user to the

first segment of the file.

FNO may appear anywhere within the input stream.

V.I. No Operation (NOP)

This operation is provided _solely_ to aid the user in formatting the

input stream, and is discarded without further processing whenever it

is encountered. In particular, a NOP embedded in a series of RTF

operations does not terminate the string as FNO does.

VI. Input Stream Format

The input stream shall consist of a contiguous string of commands to

SMFS. A command type is defined for each of the primitive file

operations of Section V. Each command has the following general

format:

8 16 32

______________//______//_________//__________//_________________//__

OP ACCESS MODIFICATION NEW

CODEFLAGSFILENAMEPASSWORD PASSWORD FILENAMEBIT COUNT DATA

____________//_____//________//_________//_______________//__

where the lengths of fixed-length fields have been indicated in bits.

Each of the fields 'FILENAME','ACCESS PASSWORD', 'MODIFICATION

PASSWORD', and 'NEW FILENAME' is further divided into the following

subfields:

8 8*LENGTH

________________________//___

LENGTH FILENAME/PASSWORD

_______________________//___

where the 'LENGTH' subfield contains the length in 8-bit characters

of the 'FILENAME/PASSWORD' subfield.

This is the _general_ format for all SMFS commands. No one command

type requires all of the fields specified above. A particular subset

of these fields is defined for each type of command, and only those

fields should appear. The defined fields for each command type are

indicated in Figure 3.

Furthermore, not all of the fields which are defined for a particular

command type need always appear _explicitly_. The user should

envision that SMFS maintains filename, password, and bit-count

accumulators. Every time a filename (or new filename),

access/modification password, or bit count appears explicitly in the

input stream, it is saved in the appropriate accumulator (a null

password -- designated by setting Bits 0,3 or Bits 8,11 to zero

(Figure 4) -- should be thought of as appearing explicitly). The

user may cause a defined field to _default_ to the current contents

of the appropriate accumulator by turning on the appropriate bin in

the flags field (see Figure 4). When a field defaults in this

manner, that field is said to appear _implicitly_ in the command.

NOP 0 No operation.

FNO 1 File no operation.

ALF 2 Allocate file.

UDF 3 Update File.

RPF 4 Replace File.

RTF 5 Retrieve File.

SPF 6 Space File.

DLF 7 Delete File.

RNF 8 Rename File.

Figure 2

Command Op codes

The three accumulators are initially empty and hence an attempt to

default a field in the first command in the input stream illicits an

error indication. A field of the appropriate type must appear once

explicitly in the input stream before the corresponding accumulator

is considered defined. Furthermore, whenever SMFS detects an invalid

filename or password (i.e., improper length or deviation from the

character set) in the input stream, the appropriate accumulator is

left empty again.

SMFS allows operations on several files to be interleaved in the

input stream by including in its command formats provision for

explicitly specifying filename and password information in each

command. When many operations involving the same file appear

sequentially in the input stream, the user need only let the

appropriate fields default in all but the first command, avoiding

re-transmission of what would otherwise be redundant parameters.

M

O

D

I

F

I

A C

C A

C T

E I N

S O E

S N W

B

F P P F I

O I A A I T

P L S S L

F E S S E C

C L N W W N O D

O A A O O A U A

D G M R R M N T

E S E D D E T A

_____________________________________________________________

ALF X X X X X X

_____________________________________________________________

UDF X X X X X X

_____________________________________________________________

RPF X X X X X X

_____________________________________________________________

RTF X X X X X

_____________________________________________________________

SPF X X X X X

_____________________________________________________________

DLF X X X X

_____________________________________________________________

RNF X X X X X

_____________________________________________________________

FNO X

_____________________________________________________________

NOP X

_____________________________________________________________

Figure 3

Defined Command Fields

Note: Command fields marked with an 'X' are defined.

0 ACCESS PASSWORD The access password for this

DEFAULTS operation defaults to the access

or modification password which

appeared explicitly most

recently in the input stream;

hence, it does not appear

explicitly in the current

command.

1 BIT COUNT DEFAULTS The bit count for this operation

defaults to that which appeared

explicitly most recently in the

input stream; hence it does not

appear explicitly in the current

command.

2 FILENAME DEFAULTS The filename for this operation

defaults to the filename or new

filename which appeared explicitly

most recently in the input stream;

hence it does not appear

explicitly in the current command.

3 ACCESS PASSWORD The access password for this

APPEARS EXPLICITLY operation appears explicitly in

the current command. (Bits 0,

3 = 0 indicates that no access

password was/is-to-be defined

for the file.)

4 ECHO OP CODE SMFS shall echo the op code and

AND FILENAME filename (whether it appears

explicitly or not) by copying

them into the output stream

ahead of any other response to

the current command.

5-7 undefined Not examined; should be zeros.

8 MODIFICATION Same as Bit 0, but applied to

PASSWORD DEFAULTS the modification password, rather

than the access password.

Figure 4

Definition of Command FLAGS Bits

9 FILE FORMATTED FOR UDF/RTF: this segment is part

of a formatted file; hence SMFS

should record the bit count. For

RTF/SPF: the referenced file is

formatted; hence the bit count

does not appear explicitly in the

current command

10 NEW FILENAME same as Bit 2, but applied

DEFAULTS to the new filename, rather

than the filename.

11 MODIFICATION PASSWORD Same as Bit 3, but applied to

APPEARS EXPLICITLY the modification password,

rather than the access

password.

12-15 undefined Not examined; should be zeros.

Figure 4(continued)

Definition of Command FLAGS Bits

Note: The sixteen bits of FLAGS are numbered 0-15 from

left to right.

When a series of RTF/SPF operations referencing the same file are

juxtaposed in the input stream (as discussed in Section V.D.), they

cause successive segments of the file to be transmitted _only_ if

both filename and access password default (Bits 0,2 = 1) (a null

password is also acceptable) in those operations following the first

in the series. If the user specifies either parameter explicitly in

a command in the series -- even if the explicitly stated value is the

same as what would have been the default value -- SMFS considers the

series terminated, as if a FNO had been encountered, and hence the

command in question returns, or flushes, the first segment of the

file. Allowing both filename and password to default has the added

effect, in both RTF/SPF and UDF series, of decreasing the processing

time required by SMFS to execute the operations which comprise the

series. Under such circumstances, SMFS executes such initial

functions as file location and password verification only once at the

beginning of the series, rather than for each operation. Hence, a

potential for increased transmission rates exists. Furthermore, in

such a series of UDF/RPF operations, SMFS is able to conserve

secondary storage by concatenating file segments before they are

written out.

Whenever SMFS aborts the processing of a command in the input stream

(e.g., the filename is invalid, an incorrect password is supplied,

etc), SMFS flushes the entire command. Suppose, for example, that

the file specified in a UDF operation does not exist (i.e., has not

been allocated). If the data field for the operation is very long,

SMFS may well detect the non-existence of the file before the data

field has been transmitted by the user. In such cases, SMFS will

accept and flush whatever remains of the aborted command (in this

case, including the very long data field) until it reaches the point

in the input stream at which it expects to find the next command,

which it will process normally. SMFS will, however, notify the user

that the command was aborted by placing an appropriate indicator in

the output stream, and it will do this as soon as it detects the

error (and hence, in this case, before the erroneous command has been

flushed from the input stream). Hence, the user has the option of

aborting the process by closing the connection.

SMFS considers a command with an invalid op code as an especially

severe error, since it has no way of locating the start of the next

command. Accordingly, it places a special character (X'FF') in the

output stream, follows it with the invalid op code, and then closes

its connections to the user.

VII. Output Stream Format

SMFS will respond to each command it extracts from the input stream

-- every command except FNO and NOP -- by placing a command response

in the output stream. Command responses have the following general

format:

8 8 32

_________//___________________________//____

OP CMPL

CODE FILENAME CODE BIT COUNT DATA

________//________________________//____

where the lengths of fixed-length fields have been indicated in bits.

The field 'FILENAME' is further divided into the following subfields:

8 8*LENGTH

_______________//______

LENGTH FILENAME

______________//______

where the 'LENGTH' subfield contains the length in 8-bit characters

of the 'FILENAME' subfield.

This is the general format for SMFS command responses. For responses

to particular commands, not all fields may be present. A particular

subset of these fields is defined for each type of command response;

no other fields will appear. The defined fields for each command

response type are indicated in Figure 5.

The fields 'OP CODE' and 'FILENAME' are the op code and filename

extracted by SMFS from the input stream and are echoed by SMFS in the

output stream. The filename is always echoed explicitly, even if it

appeared implicitly in the input stream. 'OP CODE' and 'FILENAME' are

suppressed and hence do not appear in the command response it Bit 4

of the 'FLAGS' field of the corresponding command is set to 0.

'CMPL CODE' contains an indication of the outcome of the operation.

If the operation was completed successfully, 'CMPL CODE' contains a

value equal to the op code of the command executed. Hence, if

echoing of 'OP CODE' and 'FILENAME' is not suppressed, the operation

was successful if and only if 'OP CODE' and 'CMPL CODE' are

identical. If the operation as unsuccessful, 'CMPL CODE' contains an

indication of the error encountered by SMFS in processing the

command. Completion codes are summarized in Figure 6.

C

O

M

P

L

E

F T B

I I I

O L O T

P E N

C

C N C O D

O A O U A

D M D N T

E E E T A

_____________________________________________________

NOP

_____________________________________________________

FNO

_____________________________________________________

ALF X X X

_____________________________________________________

UDF X X X

_____________________________________________________

RPF X X X

_____________________________________________________

RTF X X X X X

_____________________________________________________

SPF X X X X

_____________________________________________________

DLF X X X

_____________________________________________________

RNF X X X

_____________________________________________________

Figure 5

Defined Command Response Fields

Note: Command response fields marked with an 'X' are defined.

An invalid op code in the input stream constitutes a special type of

error. SMFS's response is as follows. A special command response is

constructed. It consists of the value X'FF' in an eight-bit field,

followed by the erroneous op code, also in an eight-bit field. The

command response is placed in the output stream and connections to

the user are closed.

2 ALLOCATION SUCCESSFUL The file was successfully allocated.

3 UPDATE SUCCESSFUL The file was successfully updated.

4 REPLACE SUCCESSFUL The file was successfully replaced.

5 RETRIEVE SUCCESSFUL The file segment was successfully

retrieved.

6 SPACE SUCCESSFUL The file segment was successfully

flushed.

7 DELETION SUCCESSFUL The file was successfully deleted.

8 RENAME SUCCESSFUL The file was successfully renamed.

20 NO DEFAULT FILENAME The user attempted to default the

filename (or new filename), and the

filename accumulator was empty.

21 ZERO-LENGTH FILENAME The length of the filename (or new

filename) was specified as zero.

22 FILENAME TOO LONG The length of the filename (or new

filename) exceeded 36 characters.

23 INVALID FILENAME The filename (or new filename)

contained character(s) that do not

appear in the character set.

24 NO DEFAULT PASSWORD The user attempted to default either

the access or modification password,

and the password accumulator was empty.

25 ZERO-LENGTH PASSWORD The length of either the access of

modification password was specified as

zero.

Figure 6

Completion Codes

26 PASSWORD TOO LONG The length of either the access or

modification password exceeded 36

characters.

27 NO DEFAULT BIT COUNT The user attempted to default the bit

count, and the bit-count accumulator

was empty.

28 INVALID PASSWORD Either the access or modification

password contained character(s) that do

not appear in the character set.

29 DUPLICATE FILENAME Either the filename (in an ALF

operation) or new filename (in a RNF

operation) is already assigned to

another file.

30 INSUFFICIENT SPACE (In an ALF operation) The requested

amount of secondary storage is

unavailable.

31 ALLOCATION I/O ERROR (In an ALF operation) An irrecoverable

I/O error was encountered by SMFS while

attempting to allocate the file.

32 FILE NOT FOUND The referenced file does not exist.

33 SEARCH I/O ERROR An irrecoverable I/O error was

encountered by SMFS while attempting to

locate the referenced file.

34 FILE FULL (In a UDF/RPF operation) The secondary

storage allocated to the file has been

exhausted.

35 INCORRECT PASSWORD The access or modification password

supplied by the user does not match

that declared when the file was

allocated.

36 FILE SIZE TOO SMALL (In an ALF operation) The bit count

specified is less than the minimum file

size accepted by SMFS.

Figure 6 (continued)

Completion Codes

37 FILE SIZE TOO BIG (In an ALF operation) The bit count

specified exceeded the maximum file

size accepted by SMFS.

38 WRITE I/O ERROR An irrecoverable I/O error as

encountered by SMFS. (In an ALF

operation) SMFS was attempting to

record password information, or (in a

UDF/RPF operation) SMFS as attempting

to add data to the file.

39 READ I/O ERROR An irrecoverable I/O error was

encountered by SMFS attempting to

retrieve either password information or

data.

40 RENAME I/O ERROR An irrecoverable I/O error was

encountered by SMFS while attempting to

rename the file.

41 DELETE I/O ERROR (In a DLF operation) An irrecoverable

I/O error was encountered by SMFS while

attempting to delete the file.

42 END-OF-DATA (In a RTF/SPR operation) The end of the

file was reached before the requested

segment had been transmitted/flushed.

Figure 6 (continued)

Completion Codes

[ This RFCwas put into machine readable form for entry ]

[ into the online RFCarchives by Gottfried Janik 2/98 ]

 
 
 
免责声明:本文为网络用户发布,其观点仅代表作者个人观点,与本站无关,本站仅提供信息存储服务。文中陈述内容未经本站证实,其真实性、完整性、及时性本站不作任何保证或承诺,请读者仅作参考,并请自行核实相关内容。
2023年上半年GDP全球前十五强
 百态   2023-10-24
美众议院议长启动对拜登的弹劾调查
 百态   2023-09-13
上海、济南、武汉等多地出现不明坠落物
 探索   2023-09-06
印度或要将国名改为“巴拉特”
 百态   2023-09-06
男子为女友送行,买票不登机被捕
 百态   2023-08-20
手机地震预警功能怎么开?
 干货   2023-08-06
女子4年卖2套房花700多万做美容:不但没变美脸,面部还出现变形
 百态   2023-08-04
住户一楼被水淹 还冲来8头猪
 百态   2023-07-31
女子体内爬出大量瓜子状活虫
 百态   2023-07-25
地球连续35年收到神秘规律性信号,网友:不要回答!
 探索   2023-07-21
全球镓价格本周大涨27%
 探索   2023-07-09
钱都流向了那些不缺钱的人,苦都留给了能吃苦的人
 探索   2023-07-02
倩女手游刀客魅者强控制(强混乱强眩晕强睡眠)和对应控制抗性的关系
 百态   2020-08-20
美国5月9日最新疫情:美国确诊人数突破131万
 百态   2020-05-09
荷兰政府宣布将集体辞职
 干货   2020-04-30
倩女幽魂手游师徒任务情义春秋猜成语答案逍遥观:鹏程万里
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案神机营:射石饮羽
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案昆仑山:拔刀相助
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案天工阁:鬼斧神工
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案丝路古道:单枪匹马
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:与虎谋皮
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:李代桃僵
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案镇郊荒野:指鹿为马
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案金陵:小鸟依人
 干货   2019-11-12
倩女幽魂手游师徒任务情义春秋猜成语答案金陵:千金买邻
 干货   2019-11-12
 
推荐阅读
 
 
 
>>返回首頁<<
 
靜靜地坐在廢墟上,四周的荒凉一望無際,忽然覺得,淒涼也很美
© 2005- 王朝網路 版權所有