Scan (SCAN)

Operand 2: Character variable scalar.

Operand 3: Character scalar.

Operand 4-5:

• Branch Form-Branch point, instruction pointer, relative instruction number, or absolute instruction number.

• Indicator Form-Numeric variable scalar or character variable scalar.

Description:   The character string value of the base operand is scanned for occurrences of the character string value of the compare operand.

The base and compare operands must both be character strings. The length of the compare operand must not be greater than that of the base string.

The operation begins at the left end of the base string and continues character by character, from left to right, comparing the characters of the base string with those of the compare operand. The length of the comparisons are equal to the length of the compare operand value and function as if they were being compared in the Compare Bytes Left-Adjusted (CMPBLA) instruction.

If a set of bytes that match the compare operand is found, the binary value for the ordinal position of its leftmost base string character is placed in the receiver operand.

If the receiver operand is a scalar, only the first occurrence of the compare operand is noted. If it is an array, as many occurrences as there are elements in the array are noted.

The operation continues until no more occurrences of the compare operand can be noted in the receiver operand or until the number of characters (bytes) remaining to be scanned in the base string is less than the length of the compare operand.

When the second condition occurs, the receiver value is set to 0. If the receiver operand is an array, all its remaining elements are also set to 0.

The base operand and the compare operand can be variable length substring compound operands.

Substring operand references that allow for a null substring reference (a length value of zero) may be specified for operands 2 and 3. The effect of specifying a null substring reference for the compare operand or both operands is that the receiver is set to zero (no match found) and the instruction's resultant condition is null compare operand. Specifying a null substring reference for just the base operand is not allowed due to the requirement that the length of the compare operand must not be greater than that of the base string.

Resultant Conditions:  

• Zero-The numeric value(s) of the receiver operand is zero. When the receiver operand is an array, the resultant condition is zero if all elements are zero. One of these two conditions will result when the compare operand is not a null substring reference.

• Positive-The numeric value(s) of the receiver operand is positive.

• Null compare operand-The compare operand is a null substring reference; therefore, the receiver has been set to zero which indicates that no occurrences were found.

Authorization Required

• None

Lock Enforcement

• None

Exceptions

06 Addressing

• 0601 Space Addressing Violation
• 0602 Boundary Alignment
• 0603 Range

08 Argument/Parameter

• 0801 Parameter Reference Violation

0C Computation

• 0C08 Length Conformance

10 Damage Encountered

• 1004 System Object Damage State
• 1044 Partial System Object Damage

1C Machine-Dependent

• 1C03 Machine Storage Limit Exceeded

20 Machine Support

• 2002 Machine Check
• 2003 Function Check

22 Object Access

• 2201 Object Not Found
• 2202 Object Destroyed
• 2203 Object Suspended
• 2208 Object Compressed
• 220B Object Not Available

24 Pointer Specification

• 2401 Pointer Does Not Exist
• 2402 Pointer Type Invalid

2C Program Execution

• 2C04 Branch Target Invalid

2E Resource Control Limit

• 2E01 User Profile Storage Limit Exceeded

36 Space Management

• 3601 Space Extension/Truncation

44 Protection Violation

• 4401 Object Domain or Hardware Storage Protection Violation
• 4402 Literal Values Cannot Be Changed