getbootpent(3X)getbootpent(3X)NAMEgetbootpent(), putbootpent(), setbootpent(), endbootpent(),
parse_bp_htype(), parse_bp_haddr(), parse_bp_iaddr() - get or put
These functions reside in libdc.a, and are linked using the option to
the or command.
These functions help a program read or modify a bootptab control) file
one entry at a time. locates an entry in the file, or an alternate
file specified to and returns a pointer to an array of objects of type
that breaks the entry into separate data fields with preceding, or
embedded, comment (text) lines.
The structure is defined in and includes the following members:
The file also defines the following data type and constants:
The fields are described in the section below. The purpose of each
function is as follows.
When first called, returns a pointer to, and the number of ele‐
ments in, an array of structures. The array
holds the first entry in the file (or from an
alternate file specified by a call to includ‐
ing leading, or embedded, comment lines. Each
subsequent 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, reads the
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
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 below.
The data remains valid until the next call of
If there are comments after the last entry,
they are returned as a separate entry with no
Opens the specified file for reading by
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, opens and
If the last file opened by (or implicitly by
was a subsequent call to for the same file
rewinds the file to the beginning, making vis‐
ible any recent changes to the file, without
first requiring a call to
Frees the in-memory copy of the last file opened by
Writes (to the current location in the stream specified by
bootpfile) the ASCII equivalent of the speci‐
fied array of structures containing one file
entry, and its leading, or embedded, comments
(a total of numfields array elements).
Entries are written in canonical form, meaning
the entry name and each data field are on sep‐
arate 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.
Converts a host address type from string to numeric format
in the same manner as
Converts a host (hardware, link level) address from string to binary
in the same manner as given a host address
type The calling program's result, which must
be an array containing at least elements, is
modified to hold the host address binary
value, and is modified to indicate the length
in bytes of the resulting address. This can
be used to compare two host addresses, inde‐
pendent of string representations. source is
modified to point to the first char after the
Converts an internet address from string to binary format in the same
This can be used to compare two internet
addresses, independent of string representa‐
tions. The calling program's result is modi‐
fied to hold the internet address binary
value. source is modified to point to the
first char after the parsed address.
If is 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 is or 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.
Entry field strings are of the form:
with surrounding whitespace, if any, removed (see bootpd(1M) for the
full description). Double quotes, and backslashes, can appear anywhere
in the field strings.
Template entries (those referred to by other entries using fields) are
not special. They can be managed like other entries. It is the call‐
ing program's responsibility to correctly manage the order of fields,
fields, and ``@'' fields that override earlier field values.
returns the number of valid array elements (one or more) upon success‐
ful completion. At the end of the input file it returns zero. If it
cannot open or close the file it returns -1. If it encounters a memory
allocation or map error, or a read error, it returns -2.
returns zero if successful opening and reading the specified or default
file. If it cannot open or close the file it returns -1. If it
encounters a memory allocation or map error or a read error it returns
returns zero if successful freeing the memory for the current open
file. If there is no current file it returns -1. If it cannot free
the memory for the current file it returns -2.
returns zero if successful writing an entry to the specified file, with
the indication clear (see ferror(3S)). Otherwise it returns non-zero
In all cases above, if a failure is due to a failed system call, the
value from the system is valid on return from the called function.
returns if the hardware type string is unrecognized.
returns zero if successful, otherwise non-zero in case of parsing
error, invalid htype, or a host address type for which the address
length is unknown; source is modified to point to the first illegal
char (a NUL if the string is too short). The caller's bytes value is
unmodified, but result might be changed.
returns zero if successful, otherwise non-zero, and source is modified
to point to the first illegal char (a NUL if the string is null).
The following code fragment copies all data and comments from to a tem‐
porary copy of the file. It converts data entries to canonical form as
a side effect, and prints to standard output the first field of each
entry copied (should be the field name, assuming the entry doesn't
start with a continuation line).
FILE *newfilep; /* to write temp file */
bpp_t bp; /* read from file */
int field; /* current field number */
int fields; /* total in array for one entry */
if ((newfilep = fopen ("/tmp/bootptab", "w")) == (FILE *) NULL)
while ((fields = getbootpent (&bp)) > 0)
for (field = 0; field < fields; ++field)
if ((bp[field].bp_type) == BP_DATA)
(void) puts (bp[field].bp_text);
if (putbootpent (bp, fields, newfilep))
if (fields < 0) /* error reading file */
if (fclose (newfilep))
The following code fragment saves a copy of a bootptab entry returned
size = fields *BP_SIZE;
if ((bpnew = (bpp_t) malloc (size)) == BP_NULLP)
(void) memcpy ((void *)bpnew, (void *)bp, size);
These functions are unsafe in multi-thread applications.
Calling releases any locks on the file it opens.
These functions were developed by HP.
control file for
SEE ALSObootpd(1M), errno(2), lockf(2), ferror(3S), fopen(3S), malloc(3C).