000000: 237777	   lac 017777 i
000001: 540407	   sad d4			" Skip if we have more than four argument words
000002: 600052	     jmp nofiles		" Only four argument words, so no arguments
000003: 217777	   lac 017777			" Move five words past the argument word count
000004: 340406	   tad d1			" so that AC points at the first argument
000005: 340407	   tad d4			" and save the pointer in name
000006: 040010	   dac name
000007: 000003	   sys open; name:0; 0		" Open file, get fd back
000010: 000000	
000011: 000000	
000012: 741100	   spa
000013: 600035	     jmp badfile		" Negative fd, exit with an error message
000014: 040301	   dac fi			" Save file descriptor in fi
000015: 100104	   jms getc			" Get a character in AC
000016: 540407	   sad o4
000017: 600022	     jmp 1f			" Break the loop when we get a ctrl-D
000020: 100140	   jms putc			" Write the character on stdout
000021: 600015	   jmp 1b			" and loop back
000022: 200301	   lac fi			" Close the file descriptor in fi
000023: 000011	   sys close
000024: 777774	   -4
000025: 377777	   tad 017777 i			" Subtract 4 from the count of argument words
000026: 077777	   dac 017777 i
000027: 540407	   sad d4			" Is the value 4, i.e. no args left?
000030: 600064	     jmp done			" Yes, so exit
000031: 200010	   lac name			" Still an argument, so move up
000032: 340407	   tad d4			" to the next filename argument
000033: 040010	   dac name
000034: 600007	   jmp loop			" and loop back to cat this file
000035: 200010	   lac name			" Get the pointer to the filename
000036: 040041	   dac 1f			" Store it in 1f below
000037: 200410	   lac d8			" Load fd 8 which is stderr
000040: 000005	   sys write; 1:0; 4		" Write the four words of the filename
000041: 000000	
000042: 000004	
000043: 200410	   lac d8
000044: 000005	   sys write; 1f; 2		" and then write " ?\n"
000045: 000050	
000046: 000002	
000047: 600024	   jmp loop1			" Now try doing the next argument
000050: 000040	1: 040;077012			" String literal: " ?\n"
000051: 077012	
000052: 200410	   lac d8
000053: 000005	   sys write; 1f; 5		" Write "No files\n" to stderr
000054: 000057	
000055: 000005	
000056: 000016	   sys exit			" and exit
000057: 156157	1: <no>; 040;  <fi>;<le>;<s 012
000060: 000040	
000061: 146151	
000062: 154145	
000063: 163012	
000064: 200404	   lac noc			" Is the number of characters left zero?
000065: 741200	   sna
000066: 000016	     sys exit			" Yes, exit
000067: 500406	   and d1
000070: 751200	   sna cla
000071: 600074	     jmp 1f
000072: 100140	   jms putc			" Print out the character
000073: 600064	   jmp done			" and loop back
000074: 200404	   lac noc			
000075: 744020	   rcr
000076: 040102	   dac 1f
000077: 200405	   lac fo			" Load fd 1, stdout
000100: 000005	   sys write; iopt+1; 1:..
000101: 000304	
000102: 000000	
000103: 000016	   sys exit
000104: 000000	getc: 0
000105: 200176	   lac ipt			" Load the pointer to the next word in the buffer
000106: 540177	   sad eipt
000107: 600123	     jmp 1f			" We've reached the end of the buffer, so read more
000110: 040174	   dac 2f			" Save the pointer
000111: 300411	   add o400000			" Flip the msb and save into ipt
000112: 040176	   dac ipt
000113: 740010	   ral				" Move the msb into the link register
000114: 220174	   lac 2f i			" Load the word from the buffer
000115: 741400	   szl				" Skip if this is the second character in the word
000116: 660511	     lrss 9			" It's the first char, shift down the top character
000117: 500412	   and o177			" Keep the lowest 7 bits
000120: 741200	   sna
000121: 600105	     jmp getc+1			" Skip a NUL characters and read another one
000122: 620104	   jmp getc i			" Return the character from the subroutine
000123: 200301	   lac fi			" Buffer is empty, read another 64 characters
000124: 000004	   sys read; iipt+1; 64
000125: 000201	
000126: 000100	
000127: 741200	   sna
000130: 600136	     jmp 1f			" No characters were read in
000131: 340200	   tad iipt			" Add the word count to the base of the buffer
000132: 040177	   dac eipt			" and store in the end buffer pointer
000133: 200200	   lac iipt			" Reset the ipt to the base of the buffer
000134: 040176	   dac ipt
000135: 600105	   jmp getc+1			" and loop back to get one character
000136: 200407	   lac o4			" No character, return with ctrl-D
000137: 620104	   jmp getc i			" return from subroutine
000140: 000000	putc: 0
000141: 500412	   and o177			" Keep the lowest 7 bits and save into 2f+1
000142: 040175	   dac 2f+1
000143: 200302	   lac opt			" Save the pointer to the empty buffer
000144: 040174	   dac 2f			" position to 2f
000145: 300411	   add o400000			" Flip the msb and save back into opt
000146: 040302	   dac opt			" This also has the effect of incrementing
000147: 741100	   spa				" If the bit was set, we already have one
000150: 600154	     jmp 1f			" character at 2f+1. If no previous character,
000151: 220174	   lac 2f i			" merge the old and new character together
000152: 240175	   xor 2f+1
000153: 600156	   jmp 3f			" and go to the "save it in buffer" code
000154: 200175	   lac 2f+1			" Move the character up into the top half
000155: 660711	   alss 9
000156: 060174	   dac 2f i			" Save the word into the buffer
000157: 440404	   isz noc			" Add 1 to the char count, never skipping
000160: 200404	   lac noc			" Have we reached 128 characters, 64 words?
000161: 540413	   sad d128
000162: 741000	     skp
000163: 620140	   jmp putc i			" No, so return (more room still in the buffer)
000164: 200405	   lac fo			" Load fd1 (i.e stdout)
000165: 000005	   sys write; iopt+1; 64	" and write out the 64 words in the buffer
000166: 000304	
000167: 000100	
000170: 200303	   lac iopt
000171: 040302	   dac opt			" Set opt pointing back to base of buffer
000172: 140404	   dzm noc			" Set the number of chars in the buffer to 0
000173: 620140	   jmp putc i			" and return
000174: 000000	2: 0;0				" Current input and output word pointers
000175: 000000	
000176: 000000	ipt: 0				" Current input buffer base
000177: 000000	eipt: 0				" Pointer to end of data read in input buffer
000200: 000201	iipt: .+1; .=.+64		" 64 word input buffer and pointer to it
000301: 000000	fi: 0				" Input file descriptor
000302: 000304	opt: .+2			" Current output buffer base
000303: 000304	iopt: .+1; .=.+64		" 64 word output buffer and pointer to it
000404: 000000	noc: 0				" Number of output characters
000405: 000001	fo: 1				" Output file descriptor, fd 1 is stdout
000406: 000001	d1: 1				" Octal and decimal constants
000407: 000004	o4:d4: 4
000410: 000010	d8: 8
000411: 400000	o400000: 0400000		" Msb toggle bit
000412: 000177	o177: 0177			" ASCII mask
000413: 000200	d128: 128			" 128 words in the output buffer