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SET STRUCTURE struc_name, FIELD field_expr: PARTIAL KEY str_expr
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10 OPEN STRUCTURE cl: NAME 'tti_run:client'
INPUT 'Name': name$
SET STRUCTURE cl, FIELD last: PARTIAL KEY name$
PRINT cl(id); ' '; cl(last)
20 END
RNH
Name? D
80561 Derringer
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This statement retrieves the first record matching the partial key in str_expr.
SET STRUCTURE struc_name: ID str_expr
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10 DECLARE STRUCTURE str
OPEN STRUCTURE cl: NAME 'tti_run:client'
ASK STRUCTURE cl: ID cl_id$
SET STRUCTURE STR: ID cl_id$
20 EXTRACT STRUCTURE str
END EXTRACT
FOR EACH str
PRINT str(#1); ' '; str(#2)
NEXT str
30 END
RNH
20000 Smith
20001 Jones
20002 Kent
23422 Johnson
32001 Waters
43223 Errant
80542 Brock
80543 Cass
80544 Porter
80561 Derringer
80573 Farmer
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SET STRUCTURE: ID sets a structure to a structure ID that you have stored previously into a string variable with the ASK STRUCTURE: ID statement. Once you have used the SET STRUCTURE: ID statement, you can access the structure with the new structure name (STR in the example). By using these statements, you can write generalized routines when you do not know which structure you are going to access until run time.
SET STRUCTURE struc_name: POINTER num_expr
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10 OPEN STRUCTURE cl: NAME 'tti_run:client'
EXTRACT STRUCTURE cl
END EXTRACT
SET STRUCTURE cl: POINTER 3
PRINT cl(id); ' ' ; cl(last)
20 END
RNH
20000 Kent
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This statement sets the structure to the nth record extracted. The statement is useful after you have done an extract, because it provides random access to any record extracted. There is no error message if there are no records extracted, or if the number given is out of range. If the number is valid, _EXTRACTED is set to 1; otherwise, it is set to 0.
SET STRUCTURE struc_name: RECORD num_expr
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10 OPEN STRUCTURE ml: NAME 'tti_run:maint_log'
SET STRUCTURE ml: RECORD 3
PRINT ml(cost)
20 END
RNH
$370.00
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SET STRUCTURE: RECORD sets the structure to the record number given. The statement works only for structures that support relative record access.
14.9.7 SET STRUCTURE: EXTRACTED 0
SET STRUCTURE struc_name: EXTRACTED 0
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10 OPEN STRUCTURE vend: NAME 'tti_run:vendor'
SET STRUCTURE vend: EXTRACTED 0
20 END
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Setting the number of records extracted to zero causes a new collection to be started. The SET STRUCTURE struc_name : EXTRACTED 0 statement is used in conjunction with the EXTRACT STRUCTURE struc_name: APPEND statement.
14.9.8 SET STRUCTURE, SET, USING: EXPRESSION 'owner'
SET STRUCTURE struc_name1, SET 'set_name', USING struc_name2: EXPRESSION 'owner'
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10 OPEN STRUCTURE class: name 'devint:intest_dbms'
20 OPEN STRUCTURE part : name 'devint:intest_dbms'
SET STRUCTURE class, SET 'class_part', USING part: EXPRESSION 'owner'
30 END
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This statement used for DBMS handling, fetches the owner of the structure specified by struc_name1. The structure specified by struc_name2 is the owner of struc_name1 with the set given in set_name.
14.9.9 SET STRUCTURE, SET: EXPRESSION 'owner'
SET STRUCTURE struc_name1, SET 'set_name': EXPRESSION 'owner'
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10 OPEN STRUCTURE class: name 'devint:intest_dbms'
20 OPEN STRUCTURE part : name 'devint:intest_dbms'
SET STRUCTURE class, SET 'class_part': EXPRESSION 'owner'
30 END
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14.9.10 SET STRUCTURE, SET, USING, FIELD: KEY
SET STRUCTURE struc_name1, SET 'set_name', USING 'struc_name2',
FIELD field_expr: KEY str_expr
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10 OPEN STRUCTURE class: name 'devint:intest_dbms'
20 OPEN STRUCTURE part : name 'devint:intest_dbms'
SET STRUCTURE class, SET 'class_part', USING part, FIELD &
class_code: KEY cl_code$
30 END
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This statement fetches the first struc_name1 record using the key given in str_expr within the set, set_name, where struc_name2 is the owner.
14.9.11 SET STRUCTURE, SET, USING
SET STRUCTURE struc_name1, SET 'set_name', USING struc_name2
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10 OPEN STRUCTURE class: name 'devint:intest_dbms'
20 OPEN STRUCTURE part : name 'devint:intest_dbms'
SET STRUCTURE class, SET 'class_part', USING part
30 END
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This statement is used for DBMS handling and fetches the first struc_name1 within a set. The record referred to by struc_name2 is the owner.
Files are places where information is stored. You can access files from within your INTOUCH programs. Files exist outside of your program. Therefore, when your program ends, the file and the information in it still exists. The next time you run the program, you can access the file, remove old information from it and store new information in it.
Files are stored on devices: disks, tapes, etc.. They are stored under file specifications, which include a device name. For information on file names and file specifications, see Section 17.1, File Specifications and the Command Language and DCL User's Guide of the OpenVMS documentation set.
The following pages describe the INTOUCH statements used to manipulate files.
OPEN #chnl_num: NAME 'file_spec'
[, ACCESS INPUT| OUTPUT | OUTIN ] [, UNFORMATTED]
[, UNIQUE] [, OPTIMIZE OFF]
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10 OPEN #1: NAME 'test_file.tmp', ACCESS OUTPUT
PRINT #1: 'This is the first line of text.'
PRINT #1: 'This is the second line of text.'
20 CLOSE #1
30 OPEN #1: NAME 'test_file.tmp', ACCESS INPUT
LINE INPUT #1: line_1$, line_2$
PRINT line_1$
PRINT line_2$
40 CLOSE #1
RNH
This is the first line of text.
This is the second line of text.
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OPEN either opens an existing file or creates a new one. #chnl_num is the channel number associated with the file. chnl_num can be any integer number in the range of 1 to 95. (0 is the channel number associated with the terminal. Channel number 0 cannot be opened or closed.) The channel number is used to refer to the file. The channel number must be unique. If a channel number is already associated with an open file, an exception is generated.
file_spec gives the file specification of the file being opened. The file specification can be any string expression.
15.1.1 OPEN Options
The OPEN statement has several options. Multiple options are separated
with commas.
15.1.1.1 ACCESS Option
The ACCESS option specifies one of three input/output
options. These options tell INTOUCH whether you want to input (read)
data, output (store) data or input and output data.
15.1.1.2 UNFORMATTED Option
When you write to a file opened as UNFORMATTED, the
writes are done without any carriage control. This allows various
character sequences to be sent to the channel without having CR/LF
(carriage return/line feed) sequences sent as well.
10 OPEN #1: NAME 'tt:', ACCESS OUTPUT, UNFORMATTED
20 FOR i = 1 TO 10
PRINT #1: i;
NEXT i
30 END
RNH 1 2 3 4 5 6 7 8 9 10
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When you specify OPTIMIZE OFF, the file is opened without any of the INTOUCH I/O optimizations.
10 OPEN #2: NAME 'report.txt', OPTIMIZE OFF
20 END
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When the UNIQUE option is used, the file is created with a unique name. These are usually temporary work or holding files for listings, etc.
10 OPEN #12: UNIQUE, ACCESS OUTPUT
20 ASK #12: NAME x$
30 PRINT x$
40 CLOSE #12
50 END
RNH
SYS$SCRATCH:TMP_B90001.TMP
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The following example illustrates how to create uniquely named files based on file_spec.
10 OPEN #12: NAME 'payroll', UNIQUE, ACCESS OUTPUT
20 ASK #12: NAME x$
30 PRINT x$
40 CLOSE #12
50 END
RNH
SYS$SCRATCH:PAYROLL_AE0001.TMP
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CLOSE [#chnl_num | ALL]
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10 OPEN #1: NAME 'test_file.lis', ACCESS OUTPUT
20 PRINT #1: 'This is the first line.'
30 PRINT #1: 'Here is the second line.'
40 CLOSE #1
50 END
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CLOSE #chnl_num closes a file. CLOSE ALL closes all files. You should close your files before your program ends.
CLOSE closes a file from further access. Once a file is closed, data cannot be stored in it or read from it. chnl_num is the channel number associated with the file. (The channel number is assigned in the OPEN statement.) The channel number can be given as any numeric expression.
15.3 PRINT #chnl_num
The PRINT #chnl_num statement writes data to a file so
the data can be referenced at a later time.
PRINT #chnl_num [, USING print_mask]: [TAB(col){, | ;}] [expr {, | ;}
[TAB(col){, | ;}] expr...]
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10 OPEN #1: NAME 'test.tmp', ACCESS OUTPUT
PRINT #1, USING '{UCASE}?': 'first line'
PRINT #1: TAB(5); 'second line'
CLOSE #1
20 OPEN #1: NAME 'test.tmp', ACCESS INPUT
LINE INPUT #1: record_1$, record_2$
PRINT record_1$
PRINT record_2$
CLOSE #1
30 END
RNH
FIRST LINE
second line
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PRINT writes data to a file. The file must be open and have a channel number associated with it. chnl_num is the channel number and it can be any numeric expression. expr is the expression being stored in the file. When INTOUCH executes a PRINT statement, it evaluates the expression and stores its value in the file. The expression is optional. A PRINT statement without an expression writes a blank line to the file.
15.4 INPUT #chnl_num: var, var...
INPUT #chnl_num: var, var...
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10 OPEN #1: NAME 'number.dat', ACCESS OUTPUT
PRINT #1: 1; 2; 3
CLOSE #1
20 OPEN #1: NAME 'number.dat', ACCESS INPUT
INPUT #1: a, b, c
PRINT a; b; c
30 CLOSE #1
40 END
RNH
1 2 3
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The INPUT #chnl_num statement is used to read the data stored in a file. The file must be open and have a channel number associated with it. The simplest version of the INPUT statement is:
INPUT #chnl_num: var
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chnl_num is the channel number associated with the file. The channel number can be any integer expression. var is the variable the data is assigned to. Each time data is input from a file, it must be assigned to a variable. The data input must match the variable's data type. INTOUCH inputs data sequentially starting at the beginning of the file.
15.4.1 Inputting Multiple Variables
One INPUT statement can be used to input data into a number of
variables. The variables in the INPUT list must be separated by commas.
INPUT #chnl_num: var, var, var...
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INTOUCH inputs data sequentially, starting from the beginning of the file. INTOUCH continues inputting data until all the variables in the list have values.
10 DIM num(10)
OPEN #1: NAME 'number.dat', ACCESS OUTPUT
20 PRINT #1: 1
PRINT #1: 2
PRINT #1: 3
30 CLOSE #1
40 OPEN #1: NAME 'number.dat', ACCESS INPUT
50 FOR i = 1 TO 3
INPUT #1: num(i)
PRINT num(i);
NEXT i
60 CLOSE #1
70 END
RNH
1 2 3
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If the variable and data types don't match, an exception will be generated.
If an attempt is made to input more data than the file contains, an exception is generated.
15.5 LINE INPUT #chnl_num: str_var, str_var...
LINE INPUT #chnl_num [, EOF num_var]: str_var, str_var...
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10 OPEN #1: NAME 'test_file.tmp', ACCESS INPUT
20 LINE INPUT #1: line_1$, line_2$
PRINT line_1$, line_2$
30 CLOSE #1
40 END
RNH
This is the first line of text. This is the second line of text.
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LINE INPUT #chnl_num reads a line of text from a file. Everything on the line including commas, quotation marks, semi-colons, etc., is accepted as part of the input line.
The file must be open and have a channel number associated with it. The simplest version of the LINE INPUT statement is:
LINE INPUT #chnl_num: str_var
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chnl_num is the channel number associated with the file. The channel number can be any integer expression. str_var is the variable to which data is being assigned. When INTOUCH executes the LINE INPUT statement, it reads a line from the file and assigns it to the string variable specified.
LINE INPUT accepts as the input data, everything from the beginning of the line up to the first line terminator. The contents of the line---including commas, quotation marks, tabs, leading and trailing spaces, etc.---are assigned to the string variable specified. A string variable must be specified. If a numeric variable is specified, an error will result. If the line being read is empty, INTOUCH assigns a null string to the string variable.
15.5.1 EOF Option
The EOF option of LINE INPUT causes INTOUCH to return
a TRUE/FALSE value indicating when the end-of-file has been reached.
This eliminates the need for an error handler when reading files. The
format is:
LINE INPUT #chnl_num, EOF num_var: str_var
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10 ven_ch = _CHANNEL
OPEN #ven_ch: NAME 'test_file.tmp'
DO
LINE INPUT #ven_ch, EOF endfile?: datafile$
IF endfile? THEN EXIT DO
PRINT 'line was: '; datafile$
LOOP
CLOSE #1
20 END
RNH
line was: This is the first line of text.
line was: This is the second line of text.
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_CHANNEL is the next available channel number.
15.5.2 Multiple Variables
LINE INPUT can be used to read several lines of data from a file. To
read more than one item, separate the string variables with commas.
Lines are read sequentially, starting from the beginning of the file,
and assigned to the variables listed.
10 OPEN #1: NAME 'test_file.tmp', ACCESS INPUT
20 LINE INPUT #1: line_1$, line_2$
PRINT '1 '; line_1$
PRINT '2 '; line_2$
30 CLOSE #1
40 END
RNH
1 This is the first line of text.
2 This is the second line of text.
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If an attempt is made to input more data than the file contains, INTOUCH generates an exception.
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