OPTIONS

Specify runtime options

WTSupported in traditional Synergy on Windows
WNSupported in Synergy .NET on Windows
USupported on UNIX
VSupported on OpenVMS
OPTIONS:"runtime_option[ ...]"

Arguments

runtime_option

An expression, in quotation marks, that contains one or more of the following options: (a)

/bufstore

Enable buffering of a set of successive stored records with no intervening READ, READS, FIND, DELETE, or WRITE statements. This option works on ISAM files stored on the client when xfServer is being used and when system option #36 is not set. (If system option #36 is set, or if the file is not an ISAM file, /bufstore is ignored.) The buffer size is the value of the SCSPREFETCH environment variable if it is set, or 8K if SCSPREFETCH is not set. (Windows and UNIX only)

/encrypt

Enforce encryption from the client side. If encryption is not enabled on the server, a “Client server error, host:xxx” ($ERR_CLNTERR) occurs. If the file is not a remote file accessed via xfServer, this option is ignored. See Using client/server encryption for more information.

/ex

Specify exclusive access for the file being opened.

/fl=length

Define the record format as fixed-length with length as the specified record size.

/io=mode[:submode]

Redefine the OPEN processing mode, where mode is the I/O mode and submode is the I/O submode in which you want to open the file. This option overrides the OPEN mode specified. The options /io=O and
/io=A open a file for exclusive access, equivalent to the compile-time output and append modes.

/nl

Specify no record locking is to be performed on the file being opened.

/nonkey_sequential

Allow direct ISAM data input, via READS, without using an index. This option enables an ISAM file's entire contents to be read in much less time than the traditional keyed sequential read. It optimizes read performance by reading 64K-sized data blocks directly from the data file and retrieving individual records in the order in which they are encountered. Due to this data caching, the only input statement supported is READS (or READ with ^FIRST, POSITION:Q_FIRST, POSITION:Q_BOF, or XCALL BEGFL provided as a file rewind). Input mode is the optimal use of this option; however, as with /sequential, operating on an active file may result in skipping records or even encountering them more than once.

This option is also allowed in update mode but requires exclusive access (either SHARE:Q_EXCL_RW or SHARE:Q_EXCL_RO). WRITE, DELETE, and STORE are allowed, but due to the intensity of the index manipulation required, excessive use of these operations on the file (50% or more) will lose the performance gained by /nonkey_sequential. Exclusive access reduces file volatility but does not completely eliminate the possibility of encountering a record more than once on variable or compressed files. Updating a record (via WRITE) may move the record to a higher file offset, allowing it to be read again. When using this mode of operation, your application will need to cope with this situation. We recommend using a TIMESTAMP key to identify record duplicates.

/sequential

Optimize sequential record access. On Synergy ISAM, this option optimizes sequential read performance by not doing a tree probe for each sequential record. On an active file (one with concurrent updates occurring), some adjacent records may not be seen at all by a READS without an intervening READ statement. In versions prior to 6.1, this was the default behavior.

/scl=level

Allow an xfServer client to specify the security compliance level, which defines which protocols will be used when encryption is enabled. Valid values for level are as follows:

0 = Always use the current Synergy default

1 = (No longer valid; removed in Synergy/DE 11.1 )

2 = Use protocols TLS 1.1, TLS 1.2, and higher

3 = Use protocols TLS 1.2 and higher (default)

If you specify 0, the current Synergy default will be used (as indicated above). This means the available protocols may change when you upgrade to a new version of Synergy. This value should be the same as the scl value set on the xfServer machine. See Using client/server encryption.

/share=value

See SHARE.

/si=size

Set the initial allocation size of the file to size. (OpenVMS only)

/stream

Specify that the file type is stream when opened for output on an OpenVMS server system.

/tf=filename

See TEMPFILE.

/guiwnd

Open a new Synergy application window through which all I/O for the channel is directed. You can use /guiwnd when opening the console (TT:). The /guiwnd option can only be used with interactive runtimes. (Windows only)

/cache

This option has been deprecated and will be ignored because, as of Synergy/DE version 10, all systems implicitly cache the index. See Index caching for details. (Windows, UNIX only)

/po

Specify the start position. See POSITION. (Windows, UNIX only)

/nodelay

Open a serial device with the UNIX O_NDELAY option. This causes the OPEN to not be blocked until the device is ready or available. The O_NDELAY flag is turned off after the device is opened so that I/O to the device does not automatically generate a “Failure during I/O operation” error ($ERR_IOFAIL). (UNIX only)

/alloc=value

See ALLOC. (OpenVMS only)

/bufnum=value

See BUFNUM. (OpenVMS only)

/bufsiz=value

See BUFSIZ. (OpenVMS only)

/deq=value

See DEQ. (OpenVMS only)

/rectype=value

See RECTYPE. (OpenVMS only)

Discussion

The OPTIONS qualifier enables you to specify one or more runtime options. These runtime options are evaluated when the OPEN is processed during program execution. Each runtime option must be enclosed in quotation marks.

The runtime options set by the OPTIONS qualifier take precedence over the other I/O qualifiers.

See also

OPEN statement

Examples

proc
    open(1, o, "TT:", options:"/guiwnd")
    writes(1, "hello")
end