HP 3000 Manuals HP 3000 Manuals
FWRITEDIR
NM and CM callable.
Writes a specific logical record from the stack to a disk file.
Syntax
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| I16V UDS I16V I32V |
| FWRITEDIR(filenum,buffer,length,lrecnum);|
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Parameters
filenum 16-bit signed integer by value (required)
Passes the file number of the file to be written
to.
buffer user-defined structure (required)
Passes the record to be written. This structure
should be large enough to hold all of the
information to be transferred.
length 16-bit signed integer by value (required)
Passes the number of half words or bytes to be
written to the file. A positive value is in half
words; a negative value is in bytes.
For files opened BUF:
* If length <= record size, the length is
transferred in half words or bytes and
remaining portions of the record is padded
with fill characters.
* If length = 0, no transfer occurs and the
record address is overwritten with default
fill characters (blanks for ASCII files;
null characters for binary files).
* If length > record size, CCL (1) is returned
and no transfer occurs.
For files opened NOBUF and nonmultirecord:
* Length is transferred in half words or bytes
up to the file limit (ignores all block
boundaries) and remaining portions of the
last block written to is padded with fill
characters.
lrecnum 32-bit signed integer by value (required)
Passes the relative number of the logical record,
or block number for NOBUF files, to be written.
Zero indicates the first record.
Operation Notes
This intrinsic differs from the FWRITE intrinsic, the FWRITE intrinsic
writes only the record pointed to by the logical record pointer. Use the
FWRITEDIR intrinsic only for disk files composed of fixed-length or
undefined-length records.
When information is written to a fixed-length record and NOBUF is not
specified in the FOPEN/HPFOPEN call that opens the file, any unused
portion of the record is padded with binary zeros or ASCII blanks.
When the FWRITEDIR intrinsic is executed, the logical record pointer is
set to the record immediately following the record just written, or the
first logical record of the next block for NOBUF files.
If RIO access is used, the modified record is set to the ACTIVE state.
When an FWRITEDIR call writes a record beyond the current logical
end-of-file indicator, the indicator is advanced. This can result in the
creation of dummy records to pad the records between the previous
end-of-file and the newly written record. When the new record is in the
same extent, these dummy records are filled with binary zeros or with
ASCII blanks.
When the physical bounds of the file prevent further writing because all
allowable extents are filled, the end-of-file condition (CCG (0)) is
returned to the program.
Not applicable to message files.
(KSAM) This intrinsic cannot be used for KSAM files. If called for a
file created as a KSAM file, CCL (1) is returned.
Condition Codes
CCE (2) Request granted.
CCG (0) Request denied. The physical end-of-file was
encountered.
CCL (1) Request denied. An error occurred.
Related Information
Intrinsics None
Commands None
Manuals Accessing Files Programmer's Guide (32650-90017)