MASK
WTSupported in traditional Synergy on Windows
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WNSupported in Synergy .NET on Windows
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USupported on UNIX
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VSupported on OpenVMS
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MASK:act_char
Arguments
act_char
An array of integers with a total size of 32 bytes and which must start on an aligned i4 boundary. (i)
Discussion
The MASK qualifier specifies activation characters at the statement level, to enable you to replace those specified by the ACCHR, ACESC, DACHR, or DAESC subroutines if you have opened a serial or terminal device other than the console (TT:). MASK is used with the GETS statement.
The act_char argument is a series of 256 bits corresponding to the ASCII character codes 0-255. If a bit is set, that character is an activation character.
To terminate on a CR or LF, for example, do the following:
1. | Create an array of 256 bits: |
actchar ,[32]i1
(Each i1 is 8 bits, and 8 x 32 = 256.)
2. | Determine the values of CR and LF (13 and 10, respectively). |
3. | Because the lowest order bit corresponds to 0 rather than 1, subtract 1 from each value (resulting in 12 and 9, respectively). |
4. | Set bit 12 and bit 9 in the array (bits 5 and 2 of the second byte, or values 16 and 2, which makes 18). |
5. | Set actchar[2] = 18. |
See also
GETS statement
Examples
The following routine sets the correct bit in the array for any specified character:
subroutine setchars ; ; Description: Routine to set the appropriate bits in the activation ; character mask for desired terminators ; ; Arguments: ; a_actchars ,[32]i1 ;Array of activation bit characters a_char ,n ;0 or more character values ; .define D_BITS_IN_CHAR ,8 ;Number of bits in a character .align stack record argnm ,i4 ;Argument counter charval ,i4 ;Character value ndx ,i4 ;Index into array group dbits ,d D_BITS_IN_CHAR ;"Bit flags" for a character dbit ,[D_BITS_IN_CHAR]d1 endgroup abits ,a D_BITS_IN_CHAR @dbits ;Union as alpha proc for argnm from ^argnum(a_char) thru %numargs ;For all "a_char" args if (^passed(^arg(argnm))) begin charval = ^argn(argnm) ;Get the character value decr charval ;Make 1 = 0 ndx = (charval / D_BITS_IN_CHAR) ;Base 0 array index charval -= (ndx * D_BITS_IN_CHAR) ;Modulo array element size clear dbits dbit[D_BITS_IN_CHAR - charval] = 1 ;Set the "bit" incr ndx ;Make the array base 1 a_actchars[ndx] = a_actchars[ndx] .bor. %b(abits) ;Mask in the bit end xreturn endsubroutine