Dot variables, so named because they begin with a period (dot), are read-only system variables useful for retrieving certain kinds of information like the date, program name, etc. In many cases, the same information is available via other methods, such as XCALLs, but the dot variable approach is generally the most elegant, efficient, and transparent. They were originally considered part of the d/Basic extensions (COMPIL /D), because most of them originated with d/Basic. But over time, A-Shell has added its own dot variables and they are now available as part of the A-Shell extensions (COMPIL/X:2).
|
Extension |
Notes |
|
.ACCOUNT |
Evaluates to the user’s current ppn (e.g. "100,22"). |
|
Number of parameters passed in the last function, procedure call, or SBX. | |
|
.DATE |
Returns the date as a decimal number which displays as MMDDYY. So March 16, 2009 should return the numeric value 31609. |
|
.DEVICE |
Evaluates to the user’s current device (e.g. "DSK0:") |
|
.EXPERIENCE |
Evaluates to the numeric value 100 (since "experience" level is not one of the AMOS job attributes that is emulated under A-Shell). |
|
.FALSE |
.TRUE and .FALSE may be used as self-documenting replacements for -1 and 0. |
|
.JOBNAME |
Evaluates to the jobname. |
|
.LAST_LABEL |
Name of last label passed. Requires ++PRAGMA TRACK_LAST_LABEL. |
|
.LAST_ROUTINE |
Name of last called function or procedure. Requires ++PRAGMA TRACK_LAST_ROUTINE. |
|
.LINENO |
Returns the last line number, similar to err(1) except without requiring an error. Not to be confused with the dot function .LINENO(ch) (which returns the physical line # since the last page break in the output file open on the specified channel). |
|
.LOCATION |
Returns the current program location counter, i.e. the offset in bytes from the start of the current program (RUN, LIT or SBX) to the current statement position. Note that the location counter is generally represented in hex (as it appears in the LSX files created by the compiler /LF switch), so you would probably want to print it using the SOSLIB function Fn'Dec2Hex(.LOCATION). |
|
.MONTH |
Evaluates to the 3 character abbreviation for the current month. |
|
.NEST_LEVEL |
Number of levels deep with nested function/procedure calls. |
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.NULL |
May be used with sequential files to open a file which is not connected to anything. |
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.PGMNAME |
Evaluates to the current program name. |
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.PGMVERSION |
Evaluates to the current program version (e.g. "1.2A(100)"). |
|
.TERMINAL |
Evaluates to the current TRMDEF name. |
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.TIME |
Evaluates to the current time, in HHMMSS format. |
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.TRUE |
.TRUE and .FALSE may be used as self-documenting replacements for -1 and 0. |
|
.USERNAME |
Evaluates to the user name. |
|
.YYMMDD |
Evaluates to the current date in YYMMDD (string) format. |
History
2016 December, A-Shell 6.3.1538, compiler edit 792: Add .LINENO and .LOCATION
2016 September, A-Shell 6.3.1524: Add special file name .NULL
2014 October, A-Shell 6.1.1391, compiler edit 710: Add .TRUE and .FALSE
2006 October, A-Shell 4.9.969: Add .LAST_LABEL, .LAST_ROUTINE, .ARGCNT, .NEST_LEVEL
1997 August, A-Shell 4.2.555: Add .TERMINAL, .JOBNAME, .USERNAME, .ACCOUNT, .DATE, .TIME, .PGMNAME, .PGMVERSION, .MONTH