HP-UX Reference (11i v2 07/12) - 3 Library Functions A-M (vol 6)

g
getbootpent(3X) getbootpent(3X)
in the /etc/bootptab
file (or from an alternate file specified by a call to
setbootpent() ), including leading, or embedded, comment lines. Each sub-
sequent call returns a pointer to the next entry in the file so that successive calls
can be used to search the entire file.
If no file is currently in memory,
getbootpent() reads the
/etc/bootptab file prior to doing its work.
The returned array exists in static space (malloc’d memory) overwritten by the
next call (so previously returned pointers become invalid). However, each array
element’s bp_text pointer points to text in an in-memory copy of the file.
This text is not altered by the next call (nor by changes to the file itself). Hence,
it is possible to copy an entry’s array in order to save it, as illustrated in EXAM-
PLES below. The data remains valid until the next call of
setbootpent()
or endbootpent()
.
If there are comments after the last entry, they are returned as a separate entry
with no data parts.
setbootpent() Opens the specified file for reading by
getbootpent(), reads a copy into
memory, and closes the file (which as a side-effect releases any locks on the file;
see lockf(2)). If the given path is a null pointer or a null string,
setboot-
pent()
opens and reads /etc/bootptab
.
If the last file opened by
setbootpent()
(or implicitly by getboot-
pent()
) was /etc/bootptab
, a subsequent call to setbootpent() for
the same file rewinds the file to the beginning, making visible any recent
changes to the file, without first requiring a call to
endbootpent()
.
endbootpent() Frees the in-memory copy of the last file opened by
setbootpent(),orget-
bootpent()
.
putbootpent() Writes (to the current location in the stream specified by bootpfile) the ASCII
equivalent of the specified array of
bootpent structures containing one file
entry, and its leading, or embedded, comments (a total of numfields array ele-
ments). Entries are written in canonical form, meaning the entry name and
each data field are on separate lines, data fields are preceded by one tab each,
and each line except the last ends with ‘‘:\’’. If numfields is less than or equal to
zero, nothing is written.
parse_bp_htype() Converts a host address type from string to numeric format (
HTYPE_*) in the
same manner as
bootpd.
parse_bp_haddr()
Converts a host (hardware, link level) address from string to binary format in
the same manner as
bootpd given a host address type (HTYPE_*). The cal-
ling program’s result, which must be an array containing at least
MAXHAD-
DRLEN
elements, is modified to hold the host address binary value, and bytes
is modified to indicate the length in bytes of the resulting address. This can be
used to compare two host addresses, independent of string representations.
source is modified to point to the first char after the parsed address.
parse_bp_iaddr() Converts an internet address from string to binary format in the same manner
as bootpd. This can be used to compare two internet addresses, independent
of string representations. The calling program’s result is modified to hold the
internet address binary value. source is modified to point to the first char after
the parsed address.
Field Definitions
If
bootpent.bp_type is BP_DATA, the associated text is one field from the current entry, either the
name field or one of the tag fields. Null tag fields (two colons in a row) are ignored, not returned.
If bootpent.bp_type is BP_COMMENT or BP_BLANK, the associated text is one comment line or
blank line from the file, either preceding the current entry or embedded in it following a data line that was
continued with a backslash. The text is exactly as it appears in the file, including any whitespace appearing
on a blank line, and there is no trailing newline.
The returned array elements are in the same order as data fields and comment lines appear in the file.
HP-UX 11i Version 2: December 2007 Update − 2 − Hewlett-Packard Company 471