There are several types of invalid SVC calls recognized by 1. Invalid SVC number. If the SVC number does not fit into any of the
four classes described above, then it is not handled byD6SITS. An
appropriate error message is displayed at the terminal, and control
is returned directly to the caller.
2. Invalid routine name inSVC 202 parameter list. If the routine
named in theSVC 202 parameter list is invalid or cannot be found, DMSITS handles the situation in the same way as it handles an error
return from a legitimateSVC routine. The error code is -3.
3. InvalidSVC 203 code. If an invalid code follows SVC 203 inline,
then an error message is displayed, and the abend routine is called
to terminate execution.SEARCH RIER!RCH! FOP. SYC When a program issues SVC 202, passing a routine or command name in the parameter list, then DMSITS must be searched for the specified routine
or command. (In the case ofSVC 203 with a zero in the table entry for
the specified index, the same logic must be applied.)
1.
The search algorithm is as follows:I check is made to see if there is a routine with
name currently occupying thesystem transient area.
case, then control is transferred there.
the specified
If this is the
2. Thesystem function name table is searched, to see if a co.mand by
this name is a nucleus-resident command. If the search is
successful, control goes to the specified nucleus routine.
3. A search is thenmade for a disk file with the specified name as
thefilename, and MODULE as the filetype. The search is made in
the standard disk search crder. If this search is successful, then
the specifiedmodule is loaded (via the LOIDMOD command), and
control passes to the storage locationnow occupied by the command. 4. If all searches so far have failed, then DftSINI (IEEREV) is called,
to see if the specified routine name is a valid system abbreviation
for asystem co •• and or function. User-defined abbreviations and
synonyms are also checked. If this search is successful, then
steps 2 through 4 are repeated with the full functionname. 5. If all searches fail, then an error code of -3 is issued. When a command is entered from the terminal, DMSINT processes the
command line, and calls the scan routine to convert it into a parameter
list consisting of eight-byte entries. The following search is
performed:
1.DMSINT searches for a disk file whose filename is the command name, and whose filetype is EXEC. If this search is successful, EXEC is
invoked to process theEXEC file.
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four classes described above, then it is not handled by
appropriate error message is displayed at the terminal, and control
is returned directly to the caller.
2. Invalid routine name in
named in the
return from a legitimate
3. Invalid
then an error message is displayed, and the abend routine is called
to terminate execution.
or command. (In the case of
the specified index, the same logic must be applied.)
1.
The search algorithm is as follows:
name currently occupying the
case, then control is transferred there.
the specified
If this is the
2. The
this name is a nucleus-resident command. If the search is
successful, control goes to the specified nucleus routine.
3. A search is then
the
the standard disk search crder. If this search is successful, then
the specified
control passes to the storage location
to see if the specified routine name is a valid system abbreviation
for a
synonyms are also checked. If this search is successful, then
steps 2 through 4 are repeated with the full function
command line, and calls the scan routine to convert it into a parameter
list consisting of eight-byte entries. The following search is
performed:
1.
invoked to process the
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