sethtitem(3alc)

1SETHTITEM(3)          MBK HASH TABLE MANAGEMENT FUNCTIONS         SETHTITEM(3)
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NAME

6       sethtitem - test and set an item in an hash table.
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SYNOPSIS

9       #include "mut.h"
10       int sethtitem(table, key)
11       ht ∗table;
12       void ∗key;
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PARAMETERS

15       table               Hash table pointer
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17       key                 Key used by the hash coding function to set an item
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DESCRIPTION

20       sethtitem() adds an item in the hash table pointed to by table, whether
21       it existed or not, and returns an appropriate value.  This is kind of a
22       test and set operator.
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RETURN VALUE

25       If  the  key  exists, the function return 1, if it doesn't, the item is
26       stored and the function returns 0.
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EXAMPLE

29       #include <stdio.h>
30       #include "mut.h"
31       checksigname(p)
32       lofig_list *p;
33       {
34       int i;
35       losig_list *ptsig;
36       locon_list *ptcon;
37       ht *h;
38       char *amatla;
39          for (i = 0, ptsig = p->LOSIG; ptsig; i++, ptsig = ptsig->NEXT);
40          h = addht(i << 1); /* half empty hash tables are faster! */
41          for (ptcon = p->LOCON; ptcon; ptcon = ptcon->NEXT)
42             addhtitem(h, ptcon->NAME, 0);
43          for (ptsig = p->LOSIG; ptsig; ptsig = ptsig->NEXT) {
44             if (ptsig->TYPE == INTERNAL) {
45                amatla = getsigname(ptsig);
46                if (!sethtitem(h, amatla, 0))
47                   printf("node %s is now unique\n", amatla);
48             }
49          }
50          delht(h);
51       }
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ERRORS

54       "∗∗∗ mbk error ∗∗∗ sethtitem impossible : value is EMPTYHT or DELETEHT"
55              The values EMPTYHT, -1,  and  DELETEHT,  -2,  are  reserved  for
56              internal use, sorry.
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DIAGNOSTICS

59       The value must be distinct from -1 and -2.
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