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  bstring(3)                          CLIX                          bstring(3)



  NAME

    bstring:  bcopy, bcmp, bzero, ffs - Provides bit/byte string operations

  LIBRARY

    Berkeley Software Distribution Library (libbsd.a)

  SYNOPSIS

    int bcopy(
      char *source ,
      char *destination ,
      int length );

    int bcmp(
      char *b1 ,
      char *b2 ,
      int length );

    int bzero(
      char *b1 ,
      int length );

    int ffs(
      int i );

  PARAMETERS

    source        Points to a source string.

    destination   Points to a destination string.

    length        Specifies the length in bytes of strings to be copied or
                  compared.

    b1            Points to a byte string.

    b2            Points to a byte string.

    i             Represents a string of bits.

  DESCRIPTION

    The bcopy(), bcmp(), and bzero() functions operate on variable-length
    strings.  They do not check for null bytes as do the functions in
    string().  The ffs() function operates on bit strings.

  EXAMPLES

    To copy one block of memory to another:



  2/94 - Intergraph Corporation                                              1

  bstring(3)                          CLIX                          bstring(3)



    char a[80],b[80];
    int i,bit;
    extern int bcopy(),bcmp(),bzero(),ffs();

    bcopy(a,b,80);

    To test two blocks for equality:

    if(bcmp(a,b,80)!=0)
         printf("Blocks not equal.\n");

    To zero out a block of memory:

    bzero(a,80);

    To find the location of the first set bit in an integer:

    bit=ffs(i);
    printf("The set bit is %d.\n",bit);


  NOTES

    The bcopy() function reverses parameters from strcpy().

  RETURN VALUES

    The bcopy() function copies length bytes from string source to the string
    destination.

    The bzero() function places length 0 bytes in the string b1.

    The bcmp() function compares byte string b1 to byte string b2, returning 0
    if they are identical, and nonzero otherwise.  Both strings are assumed to
    be length bytes long.

    The ffs() function finds the first bit set in the argument passed and
    returns the index of that bit.  Bits are numbered starting with 1.  A
    returned value of 0 indicates the value passed is 0.















  2                                              Intergraph Corporation - 2/94