MEM32 Keyword

This is used to log memory in a function compiled using 32-bit flat addressing and is coded as:

        MEM32=(address_spec,flag,{length|LEN}),

where:

address_spec

is a flat memory address specification as described in Address Specification.
flag
is a mandatory parameter that identifies the level of indirection to be used on the address. The flag may be one of the following:

D[IRECT]
I[NDIRECT][*[{+|-}iiiiiiii]]...
IS

DIRECT implies that the address specifies a memory location to be saved in the trace buffer.

INDIRECT means that the address contains a flat address and is dereferenced to obtain the memory location. The optional asterisks denote the level of indirection, one for each level. The indirect offsets iiiiiiii are added to or subtracted from the value found at the given level of indirection.

IS (Indirect Segmented) means that the address contains a segmented address that is dereferenced to obtain the memory location.

length
is the number of bytes at the memory location to be saved in the trace buffer. If length is too big, a warning message will be given, and length will be set to MAXDATALENGTH. If length is 0 an error message will be given, and this tracepoint will be ignored.
LEN
specifies that this is a variable length record to log and the length was specified by the preceding LEN statement. If there was no preceding LEN statement, this tracepoint is rejected. Either length or LEN must be specified, but not both.

The following is an example of the MEM32 statement:

     TRACE MINOR=.....           /* To log retcode enter the following: */
           MEM32=(.retcode,DIRECT,2),

           /* s_ptr is a pointer to a structure, log it for 4 bytes. */
           MEM32=(.s_ptr,INDIRECT,4),

           /* Field 6 bytes into structure pointed at by s_ptr is a     */
           /*  pointer to a structure, log 8 bytes past begin of struct.*/
           MEM32=(.s_ptr,INDIRECT*+6*+8,10),  /* logs ten bytes */

           /* s_ptr points to a variable length record, second field */
           /*  is the record length (offset 4 from record beginning).*/
           LEN=(s_ptr,INDIRECT*+4),
           MEM32=(.s_ptr,INDIRECT,LEN)

           /* s_end points to the end of same variable length record,*/
           /*  second field is the record length (offset -6 from     */
           /*  record beginning).                                    */
           LEN=(s_end,INDIRECT*-6),
           MEM32=(.s_ptr,INDIRECT,LEN)

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