Guardian Programmer's Guide

Using the File System
Guardian Programmer’s Guide — 421922-014
2 - 31
Accessing Files: An Example
?INSPECT,SYMBOLS,NOMAP,NOCODE
?NOLIST, SOURCE $SYSTEM.ZSYSDEFS.ZSYSTAL
?LIST
LITERAL MAXFLEN = ZSYS^VAL^LEN^FILENAME; !max-file name
! length
LITERAL BUFSIZE = 512;
STRING .SBUFFER[0:BUFSIZE]; !I/O buffer (one extra char)
STRING .S^PTR; !pointer to end of string
INT LOGNUM; !log file number
INT TERMNUM; !terminal file number
?NOLIST, SOURCE $SYSTEM.SYSTEM.EXTDECS0(INITIALIZER,
? PROCESS_GETINFO_,FILE_OPEN_,WRITEREADX,WRITEX,
? PROCESS_STOP_,READX,POSITION,DNUMOUT,FILE_GETINFO_)
?LIST
!------------------------------------------------------------
! These DEFINEs make it easier to format and print messages.
!------------------------------------------------------------
! Initialize for a new line:
DEFINE START^LINE = @S^PTR := @SBUFFER #;
! Put a string into the line:
DEFINE PUT^STR(S) = S^PTR ':=' S -> @S^PTR #;
! Put an integer into the line:
DEFINE PUT^INT(N) =
@S^PTR := @S^PTR '+' DNUMOUT(S^PTR,$DBL(N),10) #;
! Print the line:
DEFINE PRINT^LINE =
CALL WRITE^LINE(SBUFFER,@S^PTR '-' @SBUFFER) #;
! Print a blank line:
DEFINE PRINT^BLANK =
CALL WRITE^LINE(SBUFFER,0) #;
! Print a string:
DEFINE PRINT^STR(S) = BEGIN START^LINE;
PUT^STR(S);
PRINT^LINE; END #;