id summary reporter owner description type status priority milestone component version resolution keywords cc 373 New bit_string (bit) command/AF to manipulate bit strings in exec_coms and abbreviations Gary Dixon Gary Dixon "A new command/active function is needed to convert pl1 bit string data between radixes (binary, quaternary, octal or hexadecimal), and to adjust bit string length and output format. Documentation for the proposed program is shown below. {{{ h bit_string -all >user_dir_dir>Multics>GDixon>work>ect>bit_string.info (156 lines in info) 2025-03-05 bit_string, bit Syntax as a command: bit INPUT_STR {-control_args} Syntax as an active function: [bit INPUT_STR {-control_args}] Function: This command or active function accepts a character representation of a pl1 bit string as an input value. The program converts INPUT_STR to an actual bit string using either its ending radix indicator or the -in control argument to specify how to interpret characters of INPUT_STR. By default, the result bit string is displayed or returned as a pl1 quoted bit string with a binary radix factor: ""10011""b Arguments: INPUT_STR is the character representation of the input bit string. It may end with one of the radix indicators shown below. INDICATOR Description ------------- ------------------------------------------------- b or _b or b1 INPUT_STR is binary characters from 0 thru 1 q or _q or b2 INPUT_STR is quaternary characters from 0 thru 3 o or _o or b3 INPUT_STR is octal characters from 0 thru 7 x or _x or b4 INPUT_STR is hexadecimal characters from 0 thru f in upper- or lower-case. The b4 indicator may be used only if INPUT_STR has double-quote ("") characters surrounding the numeric digits. Without these quotes, the b4 radix_indicator would be treated as digits in the INPUT_STR string. Control arguments: -in RADIX_INDICATOR controls how characters of INPUT_STR are interpreted, unless that string ends with its own radix_indicator substring. An indicator can specify binary, quaternary, octal or hexadecimal characters in the INPUT_STR. See the ""List of radix_indicator substrings"" section for details. (default: octal input) -out RADIX_INDICATOR displays or returns the result bit string as a character string using characters of one of the power-of-2 bases. See the ""List of radix_indicator substrings"" section for details. (default: binary output) -length L, -ln L gives a desired bit length for the resulting bit string. By default, each INPUT_STR character is converted to B-bits according to its designated input radix: Radix B ----------- -------------------- binary 1 bit per character quaternary 2 bits per character octal 3 bits per character hexadecimal 4 bits per character Result default length D = B * length(INPUT_STR). If INPUT_STR ends with its own radix_indicator substring, that substring is excluded from the length(INPUT_STR) determination. If L is greater than the default length D, then L-D zero bits are appended to the right end of the result. If L is less than the default length D, then D-L bits are removed from the right end of the result. -quote, -q display or return the result as a pl1 quoted bit string with trailing radix factor. (default) For example: ""1011""b or ""23""b2 or ""54""b3 or ""b""b4 -no_quote, -nq display or return the result as a character string without surrounding quote characters or pl1 radix factor: 1011 or 23 or 54 or b -radix display or return the result as a character string without surrounding quote characters but with a radix indicator: 1011_b or 23_q or 54_o or b_x List of radix_indicator substrings: INPUT_STR may end with one of the following strings which indicate which numbering system's digits are expressing the value. Indicator characters may also be given in uppercase. -in and -out may be followed by any of the values below; but values beginning with underscore (_) are not usually given with these -control_args. b1, b, _b the number is interpreted as a base two string (binary). b2, q, _q the number is interpreted as a base four string (quaternary). b3, o, _o the number is interpreted as a base eight string (octal). b4, x, _x the number is interpreted as a base sixteen string (hexadecimal). The b4 format may be used only if INPUT_STR has double-quote ("") characters surrounding the numeric digits. Without these quotes, the b4 radix factor would be treated as digits in the INPUT_STR string. Notes: To express a result bit string in a non-binary radix, each output digit represents a group of B-bits in the result (where B is 2, 3, or 4). If the length of the result is not evenly divisible by B, then a stringsize condition is signalled. If the on-unit handing this condition returns to the point of error, then length of the result is extended by adding B - mod(L, B) zeros to the right end of the result to enable correct display of the last digit in the result. Note that the system default handler for stringsize silently returns to the point of error, thus enabling a correct result to be displayed. Examples: To convert an octal output word from the ring_zero_dump command as a binary bit string: string [ring_zero_dump 71|3357 0 1] 400000000000 bit_string [ring_zero_dump 71|3357 0 1] -in o ""100000000000000000000000000000000000""b This same result could be displayed for this input if a trailing radix indicator string were given at the end of the first argument. bit [ring_zero_dump 71|3357 0 1]o ""100000000000000000000000000000000000""b Since the default INPUT_RADIX is octal and the default OUTPUT_RADIX is binary, only the INPUT_STR need be given. bit [ring_zero_dump 71|3357 0 1] ""100000000000000000000000000000000000""b To express an octal bit string properly in hexadecimal, ""0""b bits must be added to the input bit string to fill out the final hex digit. This is shown in the example below. bit 051o ""000101001""b bit 051o -length 12 ""000101001000""b bit 051o -length 12 -out b4 ""148""b4 Extending the length of the result bit string would occur with the default handling for the stringsize condition, as shown below. bit 051 -out b4 ""148""b4 }}} " enhancement closed major MR12.9 Tools MR12.8 fixed