contrib/zlib/zlib.h

119     Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
120     uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
122     Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
124     Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
145      zalloc must return Z_NULL if there is not enough memory for the object.
148    Z_NULL on entry to the initialization function, they are set to internal
212 #define Z_NULL  0  /* for initializing zalloc, zfree, opaque */
232    zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
355   if next_in or next_out was Z_NULL or the state was inadvertently written over
385    first call).  If zalloc and zfree are set to Z_NULL, inflateInit updates
509   next_in or next_out was Z_NULL, or the state was inadvertently written over
649    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
663    Z_NULL, then only the dictionary length is returned, and nothing is copied.
664    Similary, if dictLength is Z_NULL, then it is not set.
691    (such as zalloc being Z_NULL).  msg is left unchanged in both source and
703    stream state was inconsistent (such as zalloc or state being Z_NULL).
785    or bits are Z_NULL, then those values are not set.
817    caller must assure that, if not Z_NULL, name and comment are terminated with
818    a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
901    parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
916    Z_NULL, then only the dictionary length is returned, and nothing is copied.
917    Similary, if dictLength is Z_NULL, then it is not set.
954    (such as zalloc being Z_NULL).  msg is left unchanged in both source and
965    stream state was inconsistent (such as zalloc or state being Z_NULL).
978    stream state was inconsistent (such as zalloc or state being Z_NULL), or if
1046    was valid if done is set to one.) If extra is not Z_NULL, then extra_max
1050    If name is not Z_NULL, then up to name_max characters are written there,
1052    comment is not Z_NULL, then up to comm_max characters are written there,
1054    of extra, name, or comment are not Z_NULL and the respective field is not
1055    present in the header, then that field is set to Z_NULL to signal its
1077    before the call.  If zalloc and zfree are Z_NULL, then the default library-
1143    calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
1144    immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
1160    using strm->next_in which will be Z_NULL only if in() returned an error.  If
1161    strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
1692    return the updated checksum.  If buf is Z_NULL, this function returns the
1700      uLong adler = adler32(0L, Z_NULL, 0);
1729    updated CRC-32.  If buf is Z_NULL, this function returns the required
1735      uLong crc = crc32(0L, Z_NULL, 0);