O

*OS

A global constant holding the name of the operating system. Possible values include "Linux", "FreeBSD", "Darwin" or "Cygwin".

: *OS
-> "Linux"

(obj (typ var [hook] val ..) var2 val2 ..) -> obj

Finds or creates a database object (using request) corresponding to (typ var [hook] val ..), and initializes additional properties using the varN and valN arguments.

: (obj ((+Item) nr 2) nm "Spare Part" sup `(db 'nr '+CuSu 2) inv 100 pr 1250)
-> {3-2}

(object 'sym 'typ ['sym 'any ..]) -> obj

Defines sym to be an object of type typ. The property list is initialized with all optionally supplied key-value pairs. See also OO Concepts, new, type and isa.

: (object 'Obj '(+A +B +C) 'a 1 'b 2 'c 3)
-> Obj
: (show 'Obj)
Obj (+A +B +C)
   c 3
   b 2
   a 1
-> Obj

(oct 'num) -> sym
(oct 'sym) -> num

Converts a number num to an octal string, or an octal string sym to a number. See also hex and format.

: (oct 73)
-> "111"
: (oct "111")
-> 73

(off sym ..) -> NIL

Stores NIL in the VAL's of all argument symbols sym. See also on, onOff, zero and one.

: (off A B)
-> NIL
: A
-> NIL
: B
-> NIL

(offset 'lst1 'lst2) -> cnt | NIL

Returns the cnt position of the tail list lst1 in lst2, or NIL if it is not found. See also index.

: (offset '(c d e f) '(a b c d e f))
-> 3
: (offset '(c d e) '(a b c d e f))
-> NIL

(on sym ..) -> T

Stores T in the VAL's of all argument symbols sym. See also off, onOff, zero and one.

: (on A B)
-> T
: A
-> T
: B
-> T

(one sym ..) -> 1

Stores 1 in the VAL's of all argument symbols sym. See also zero, on, off and onOff.

: (one A B)
-> 1
: A
-> 1
: B
-> 1

(onOff sym ..) -> flg

Logical negates the VAL's of all argument symbols sym. Returns the new value of the last symbol. See also on, off, zero and one.

: (onOff A B)
-> T
: A
-> T
: B
-> T
: (onOff A B)
-> NIL
: A
-> NIL
: B
-> NIL

(open 'sym) -> cnt | NIL

Opens the file sym in read/write mode, and returns a file descriptor cnt (or NIL on error). If the file does not exist, it is created. The file descriptor can be used in subsequent calls to in and out. See also close.

: (open "x")
-> 3

(opid) -> pid | NIL

Returns the corresponding process ID when the current output channel is writing to a pipe, otherwise NIL. See also ipid and out.

: (out '(cat) (call 'ps "-p" (opid)))
  PID TTY          TIME CMD
 7127 pts/3    00:00:00 cat
-> T

(opt) -> sym

Return the next command line argument (option) as a string, and remove it from the remaining command line arguments. See also Invocation and argv.

$ ./p  -"de f () (println 'opt (opt))"  -f abc  -bye
opt "abc"

(or 'any ..) -> any

Logical OR. The expressions any are evaluated from left to right. If a non-NIL value is encountered, it is returned immediately. Else the result of the last expression is returned.

: (or (= 3 3) (read))
-> T
: (or (= 3 4) (read))
abc
-> abc

(out 'any . prg) -> any

Opens any as output channel during the execution of prg. The current output channel will be saved and restored appropriately. If the argument is NIL, standard output is used. If the argument is a symbol, it is used as a file name (opened in "append" mode if the first character is "+"). If it is a positve number, it is used as the descriptor of an open file. If it is a negative number, the saved output channel such many levels above the current one is used. Otherwise (if it is a list), it is taken as a command with arguments, and a pipe is opened for output. See also opid, call, in, pipe, ctl, close and load.

: (out "a" (println 123 '(a b c) 'def))      # Write one line to file "a"
-> def