ProvideX V8.20 > Language Reference > 3. System Functions

532

TCB( ) Function

         Return Task Information

Formats

1. Return Task Information: TCB(tcb_code[,ERR=stmtref])

2. Return Activation Information: TCB(pkg_index,info_reqd[,ERR=stmtref])

3. Return Platform/User Information: TCB(keyword [,arg] [,ERR=stmtref])

Where:

arg

Argument associated with keyword (if required).

info_reqd

Any of the following values: 0 - actual package number, 1 - expiry date,

2- package activation flags.

pkg_index     A number from 0 to the number of packages installed.

keyword

Keyword requesting specific platform or user information.

stmtref

Program line number or label to transfer control to.

tcb_code

Numeric code indicating what type of information is to be returned.

Description

The TCB( ) function returns information for several different purposes. A single tcb_code

specified in the TCB( ) function returns a corresponding system control value ­ see

Format 1: Return Task Information. Two numeric codes (pkg_index,info_reqd) are

required for activation/licensing information ­ see Format 2: Return Activation

Information. Specific keywords are used to return specific information from the OS -

See Format 3: Return Platform/User Information.

Format 1: Return Task Information

TCB(tcb_code[,ERR=stmtref])

When TCB( ) is used with a single code (tcb_code), it returns task information in the

form of a numeric system control value. The codes and their values are listed below:

TCB( ) Return Values

0

Zero (0) - Reserved

1

Zero (0) - Reserved

2

Zero (0) - Reserved

3

Internal system error code.

4

Current statement number. (In a running program, not Command mode.)

5

The line number of the last error.

SETESC statement number.

6

SETERR statement number.

7

Top statement number in GOSUB stack.

8

9

Zero (0) - Reserved for future use.