[an error occurred while processing this directive]

HP OpenVMS Systems Documentation

Content starts here

HP OpenVMS DCL Dictionary


Previous Contents Index


DEPOSIT

Replaces the contents of the specified locations in virtual memory and displays the new contents.

The DEPOSIT command, together with the EXAMINE command, aids in debugging programs interactively. The DCL command DEPOSIT is similar to the DEPOSIT command of the OpenVMS Debugger.

Requires user-mode read (R) and write (W) access to the virtual memory location whose contents you wish to change.


Format

DEPOSIT location=data[,...]


Parameters

location

Specifies the starting virtual address or range of virtual addresses (where the second address is larger than the first) whose contents are to be changed. A location can be any valid integer expression containing an integer value, a symbol name, a lexical function, or a combination of these entities. Radix qualifiers determine the radix in which the address is interpreted; hexadecimal is the initial default radix. Symbol names are always interpreted in the radix in which they were defined. The radix operators %X, %D, or %O can precede the location. A hexadecimal value must begin with a number (or be preceded by %X).

The specified location must be within the virtual address space of the image currently running in the process.

The DEPOSIT and EXAMINE commands maintain a pointer to a current memory location. The DEPOSIT command sets this pointer to the byte following the last byte modified; you can refer to this pointer by using a period (.) in subsequent EXAMINE and DEPOSIT commands. If the DEPOSIT command cannot deposit the specified data, the pointer does not change. The EXAMINE command does not change the value of the pointer.

data[,...]

Specifies the data to be deposited into the specified locations. By default, the data is assumed to be in hexadecimal format; it is then converted to binary format and is written into the specified location.

If you specify more than one item, separate the items with commas (,). The DEPOSIT command writes the data in consecutive locations, beginning with the address specified.

When non-ASCII data is deposited, you can specify each item of data using any valid integer expression.

When ASCII data is deposited, only one item of data is allowed. All characters to the right of the equal sign are considered to be part of a single string. The characters are converted to uppercase, and all spaces are compressed.


Description

When the DEPOSIT command completes, it displays both the virtual memory address into which data is deposited and the new contents of the location, as follows:


address:  contents 

If the specified address can be read from but not written to by the current access mode, the DEPOSIT command displays the original contents of the location. If the specified address can be neither read from nor written to, the DEPOSIT command displays asterisks (*) in the data field. The DEPOSIT command maintains a pointer at that location (at the byte following the last byte modified).

If you specify a list of numeric values, some but not all of the values may be successfully deposited before an access violation occurs. If an access violation occurs while ASCII data is being deposited, nothing is deposited.

Radix Qualifiers: The radix default for a DEPOSIT or EXAMINE command determines how the command interpreter interprets numeric literals. The initial default radix is hexadecimal; all numeric literals in the command line are assumed to be hexadecimal values. If a radix qualifier modifies the command, that radix becomes the default for subsequent EXAMINE and DEPOSIT commands, until another qualifier overrides it. For example:


$ DEPOSIT/DECIMAL 900=256
00000384:  256

The DEPOSIT command interprets both the location 900 and the value 256 as decimal. All subsequent DEPOSIT and EXAMINE commands assume that numbers you enter for addresses and data are decimal. Note that the DEPOSIT command always displays the address location in hexadecimal.

Symbol values defined by = (assignment statement) commands are always interpreted in the radix in which they were defined.

Note that hexadecimal values entered as deposit locations or as data to be deposited must begin with a numeric character (0 to 9); otherwise, the command interpreter assumes that you have entered a symbol name and attempts symbol substitution.

You can use the radix operators %X, %D, or %O to override the current default when you enter the DEPOSIT command. For example:


$ DEPOSIT/DECIMAL %X900=10

This command deposits the decimal value 10 in the location specified as hexadecimal 900.

Length Qualifiers: The initial default length unit for the DEPOSIT command is a longword. If a list of data values is specified, the data is deposited into consecutive longwords beginning at the specified location. If a length qualifier modifies the command, that length becomes the default for subsequent EXAMINE and DEPOSIT commands, until another qualifier overrides it. If you specify data values that are longer than the specified length, an error occurs.

Length qualifiers are ignored when ASCII values are deposited.

Restriction on Placement of Qualifiers: The DEPOSIT command analyzes expressions arithmetically. Therefore, qualifiers, which must be preceded by a slash (/), must appear immediately after the command name to be interpreted correctly.


Qualifiers

/ASCII

Indicates that the specified data is ASCII.

Only one data item is allowed; all characters to the right of the equal sign (=) are considered to be part of a single string. Unless they are enclosed within quotation marks (" "), characters are converted to uppercase and multiple spaces are compressed to a single space before the data is written in memory.

The DEPOSIT command converts the data to its binary equivalent before placing it in virtual memory. When you specify /ASCII, or when ASCII mode is the default, the location you specify is assumed to be hexadecimal.

/BYTE

Requests that data be deposited 1 byte at a time.

/DECIMAL

Indicates that the data is decimal. The DEPOSIT command converts the data to its binary equivalent before placing it in virtual memory.

/HEXADECIMAL

Indicates that the data is hexadecimal. The DEPOSIT command converts the data to its binary equivalent before placing it in virtual memory.

/LONGWORD

Requests that data be deposited a longword at a time.

/OCTAL

Indicates that the data is octal. The DEPOSIT command converts the data to its binary equivalent before placing it in virtual memory.

/WORD

Requests that the data be deposited one word at a time.

Examples

#1

$ RUN MYPROG
   .
   .
   .
 
[Ctrl/Y]
$ EXAMINE %D2145876444
7FE779DC:  0000000000
$ DEPOSIT .=17
7FE779DC:  0000000017
$ CONTINUE
 
      

The RUN command executes the image MYPROG.EXE; subsequently, Ctrl/Y interrupts the program. Assuming that the initial defaults of the /HEXADECIMAL and /LONGWORD qualifiers are in effect, the DEPOSIT command places a longword value 17 (23 decimal) in virtual memory location 2145876444.

Because the EXAMINE command sets up a pointer to the current memory location, which in this case is virtual address 2145876444, you can refer to this location with a period (.) in the DEPOSIT command.

The CONTINUE command resumes execution of the image.

#2

$ DEPOSIT/ASCII   2C00=FILE: NAME: TYPE:
00002C00:  FILE: NAME: TYPE:...
 
      

In this example, the DEPOSIT command deposits character data at hexadecimal location 2C00 and displays the contents of the location after modifying it. Because the current default length is a longword, the response from the DEPOSIT command displays full longwords. The ellipsis (...) indicates that the remainder of the last longword of data contains information that was not modified by the DEPOSIT command.

#3

$ EXAMINE 9C0             !  Look at Hex location 9C0
000009C0:  8C037DB3
$ DEPOSIT .=0             !  Deposit longword of 0
000009C0:  00000000
$ DEPOSIT/BYTE .=1        !  Put 1 byte at next location
000009C4:  01
$ DEPOSIT .+2=55          !  Deposit 55 next
000009C7:  55
$ DEPOSIT/LONG .=0C,0D,0E !  Deposit longwords
000009C8:  0000000C 0000000D 0000000E
 
      

The sequence of DEPOSIT commands in the above example illustrates how the DEPOSIT command changes the current position pointer. Note that after you specify the /BYTE qualifier, all data is deposited and displayed in bytes, until the /LONGWORD qualifier restores the system default.

#4

$ BASE=%X200               !  Define a base address
$ LIST=BASE+%X40           !  Define offset from base
$ DEPOSIT/DECIMAL LIST=1,22,333,4444
00000240:  00000001 00000022 00000333 00004444
$ EXAMINE/HEX LIST:LIST+0C !  Display results in hex
00000240:  00000001 00000016 0000014D 0000115C
 
      

The assignment statements define a base address in hexadecimal and a label at a hexadecimal offset from the base address. The DEPOSIT command reads the list of values and deposits each value into a longword, beginning at the specified location. The EXAMINE command requests a hexadecimal display of these values.


Previous Next Contents Index