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Transfers a record of data to a file on any device. Syntax | |
FWRITE(filenum,buffer,length,controlcode); |
Use | |
The FWRITE intrinsic transfers a logical record of data to
a file on any device. When programming for asynchronous devices
this means writing data to a terminal or printer. Completion status
is indicated by condition codes, which your program should always
check. This intrinsic is completed "logically";
that is, once data is passed to an output buffer the call is considered
to have completed and control is returned to the calling program.
If the operation of the output device has been suspended through
flow control, the actual writing of the data may not have taken
place. There is no programmatic way to determine that printing has
taken place. Parameters | |
- filenum
16-bit signed integer by value (required) The file number of the file to be written to. - buffer
user-defined structure (required) Passes the record to be written. - length
16-bit signed integer by value (required) The number of halfwords or bytes to be written to the record.
If this value is positive, it signifies halfwords; if negative,
bytes. If the number is zero, no data transfer will occur. | | | |  | NOTE: Whether or not "bytes" is specified,
the physical data transfer will be on a byte-by-byte basis for an
asynchronous device. If halfwords are specified, an "even"
number of bytes are output. | | | | |
- controlcode
16-bit unsigned integer by value (required) This parameter indicates the carriage control action to be
used when the file is transferred to a line printer or terminal
(including a spooled file whose ultimate destination is a line printer
or terminal). This parameter is effective only for files opened
with carriage control (CCTL) specified
in the FOPEN or HPFOPEN call. The controlcode parameter may contain
0, 1,
or one of the octal codes from Table 8-11 “Selected
Carriage Control Directives”.
These options are used to indicate carriage control action as follows: - 0
Print the full record transferred, using single
spacing. This results in a maximum of 132 characters per printed
line. - 1
Use the first character of the data written to satisfy
space control and suppress this character on the printed output.
The results are a maximum of 132 characters of data per printed
line. The values permissible for use as the first character to specify
control are the same as the octal values described below, and listed
in Table 8-11 “Selected
Carriage Control Directives”.
When one of the octal codes listed in Table 8-11 “Selected
Carriage Control Directives” is used as the value of controlcode
the carriage control action associated with the specific code is
applied to the data being transferred. (You must have specified
CCTL through the FOPEN or HPFOPEN
call, or through an overriding :FILE command.)
The full record transferred is then printed, with a maximum of 132
characters per printed line. If the file being written is not a spooled file, (that is,
it is not written to disk before being output to the device), all
of the octal codes listed in Table 8-11 “Selected
Carriage Control Directives”
can also be passed through FCONTROL(1). A carriage control directive passed through FCONTROL(1) takes
effect whether or not CCTL was
specified for the file. For spooled files, however, carriage control must be set using
FWRITE. Additionally, the prespace/postspace control normally set
through FCONTROL must be set through FWRITE for spooled files. You
can use control codes %100 through %103 and %400 through %403 for
this purpose. If the controlcode parameter is not
0 or 1, and length is 0, only the space control
is executed and no data is transferred. The default carriage control is postspacing with automatic
page eject. This applies to all Hewlett-Packard supported subsystems,
with the exception of FORTRAN77/iX and COBOLII/iX, which have prespacing
with automatic page eject.
Table 8-11 Selected
Carriage Control Directives | Octal Code | Carriage |
|---|
| %2-%52 | Single space (with or without automatic page
eject). | | %53 | No space, (next printing at column 1). | | %54 | Single space (with or without automatic page
eject). | | %60 | Double space (with or without automatic page
eject). | | %61 | Conditional page eject (form feed) is performed
by the software. If the printer is not already at the top of the
form, a page eject is performed. Ignored if: | Postspace mode:
The current request has a transfer count of 0 and the current request
was FOPEN (or HPFOPEN), FCLOSE, or FWRITE specifying a carriage
control directive of %61.
| Prespace mode:
The previous request has a transfer count of 0, and the current
request and previous request are any combination of FOPEN (or HPFOPEN),
FCLOSE, or FWRITE specifying a carriage control directive of %61.
| | %62-%77 %104-%177 | Single space (with or without automatic page
eject). | | %2nn | Space nn lines (no automatic page eject); nn
is any octal number from 0 through 77. | | %300 | Skip to top of form (page eject). | | %301 | Skip to bottom of form. | | %302 | Single spacing with automatic page eject. | | %303 | Skip to next odd line with automatic page eject. | | %304 | Skip to next third line with automatic page
eject. | | %305 | Skip to next 1/2 page. | | %306 | Skip to next 1/4 page. | | %307 | Skip to next 1/6 page. | | %310 | Skip to bottom of form. | | %311 | Skip to one line before bottom of form. | | %312 | Skip to one line before top of form. | | %313 | Skip to top of form (same as %300). | | %314 | Skip to next seventh line with automatic page
eject. | | %315 | Skip to next sixth line with automatic page
eject. | | %316 | Skip to next fifth line with automatic page
eject. | | %317 | Skip to next fourth line with automatic page
eject. | | %320 | No space, no return (next printing physically
follows this). | | %321-%377 | Single space (with or without automatic page
eject). | | %400 or %100 | Sets postspace movement option; this first
print, then spaces. If previous option was prespace movement, the
driver outputs a one line advance (equivalent to an octal code of
%201 without automatic page eject) to clear the buffer. | | %401 or %101 | Sets prespace movement option; this first spaces,
then prints. | | %402 or %102 | Sets single-space option, with automatic page
eject (60 lines per page). | | %403 or %103 | Sets single-space option, without automatic
page eject (66 lines per page). |
| | | | | NOTE: If you select octal codes %55 and %60 with automatic
page eject in effect (by default or following an octal code of %102
or %402), the resulting skip across a page boundary is to the top
of the page. If automatic page eject is not in effect, a true double
or triple space results, but the perforation between pages is not
automatically skipped. | | | | |
- CCE
Request granted. - CCG
Physical EOF. Should not occur for terminals or
printers. - CCL
Request denied due to an error condition. Use FCHECK
to obtain details.
Additional Discussion | |
See the discussion of FCONTROL(1) in this manual. See also
the MPE/iX Intrinsics Reference Manual. |
