#-h- isamsym          111 asc 17-oct-80 13:33:49
 define(DEFAULT_WIDTH,25)
 define(DEFAULT_DIF,1)
 define(DEFAULT_JUSTFY,LEFT)
 define(LEFT,0)
 define(RIGHT,1)
#-h- cisam            211 asc 17-oct-80 13:33:49
 common / cisam / dif, width, justfy

 integer dif		# number of records between isam'ed records
 integer width		# width of key field in index
 integer justfy		# type of justification desired on key; init = LEFT
#-h- isam.r          2247 asc 17-oct-80 13:33:50
#-h- main             652 asc 17-oct-80 09:02:03
 include isamsym

 subroutine main

 integer oldadr(2), addr(2), n, status, i, junk
 integer getlin, getwrd, doline
 character oldwrd(MAXLINE), buf(MAXLINE), word(MAXLINE)

 include cisam

 call getcmd			# crack command line
 oldwrd(1) = EOS
 oldadr(1) = 0
 oldadr(2) = 0
 n = 0
 repeat
    {
    call markl(STDIN, addr)
    status = getlin(buf, STDIN)
    if (status != EOF)
	{
	n = n + 1
	i = 1
	junk = getwrd(buf, i, word)
	if (doline(n) == YES)
	    call outlin(word, addr)
	call scopy(word, 1, oldwrd, 1)
	oldadr(1) = addr(1)
	oldadr(2) = addr(2)
	}
    }
 until (status == EOF)
 if (doline(n) == NO)
    call outlin(oldwrd, oldadr)

 return
 end
#-h- doline           159 asc 17-oct-80 08:48:29
 integer function doline(n)

 integer n

 include cisam

 if (dif == 1)
    return(YES)
 else if (mod(n, dif) == 1)
    return(YES)
 else
    return(NO)

 end
#-h- outlin           428 asc 17-oct-80 08:48:30
 subroutine outlin(word, addr)

 character word(ARB)
 integer addr(2), j
 integer length

 include cisam

 if (justfy == RIGHT)
    for (j=length(word) + 1; j <= width; j=j+1)
	call putc(BLANK)
 call putlin(word, STDOUT)
 if (justfy == LEFT)
    for (j=length(word) + 1; j <= width; j=j+1)
	call putc(BLANK)
 call putc(BLANK)
 call putdec(addr(1), 1)
 call putc(BLANK)
 call putdec(addr(2), 1)
 call putc(NEWLINE)

 return
 end
#-h- getcmd           812 asc 17-oct-80 09:13:59
 subroutine getcmd

 character arg(FILENAMESIZE)
 integer getarg, equal, ctoi
 integer i, j

 include cisam

 string quest "?"

 dif = DEFAULT_DIF
 width = DEFAULT_WIDTH
 justfy = DEFAULT_JUSTFY

 for (i=1; getarg(i, arg, FILENAMESIZE) != EOF; i=i+1)
    {
    call fold(arg)
    if (equal(arg,quest) == YES)
	call error("usage:  isam [-d<dif>] [-w<width>] [-j<l/r>].")
    if (arg(1) == MINUS)
	switch (arg(2))
	    {
	    case LETD:
		{
		j = 3
		dif = ctoi(arg, j)
		if (dif <= 0)
		    dif = DEFAULT_DIF
		}
	    case LETW:
		{
		j = 3
		width = ctoi(arg, j)
		if (width <= 0)
		    width = DEFAULT_WIDTH
		}
	    case LETJ:
		{
		if (arg(3) == LETL)
		    justfy = LEFT
		else if (arg(3) == LETR)
		    justfy = RIGHT
		}
	    default:	call badarg(arg)
	    }
    else
	call badarg(arg)
    }

 return
 end