Topic: How to write a 32-bit number into a file

[baitang36]

Code - Auto/Visual Lisp: [Select]

1. (defun tt ()
2.   (setq aa (open "d:/tt.txt" "w"))
3.   (write-long 943208504 aa)
4.   (close aa)
5. )
6. (tt)

It is wrong to write in this way. How can we make it not wrong?

[Lee Mac]

(write-line (itoa 943208504) aa)

Or, for integers greater than 2,147,483,647 (2³¹ - 1):

(write-line (rtos 943208504 2 0) aa)

[ribarm]

Just to inform, FYI...
(rtos num 2 0) can give undesired results when number is enormously large, i.e. (around 1e+15 or 1e+16)... Test it with some still writable number that don't exceed numerical notation...

We can conclude - everything you do in ACAD, you must do in some legit limits (neither too big numbers nor too small - 1e-15) - no wonder that many have asked why for ex. IntersectWith method don't find intersections - their DWGs contained reference curves far away from 0,0,0 origin point (1e+10 or similar)...

[d2010]

Or  How to write directly ?
(Setq dectoint 0xFFAFEAD)
(Setq LeeMac (+ 0xFFAFEAD 0x1FAFEAD))
(Alert "Can you use hexadecimals without convert Dec2Int?")
 

(write-line (itoa 943208504) aa)
Or, for integers greater than 2,147,483,647 (2³¹ - 1):
(write-line (rtos 943208504 2 0) aa)

[baitang36]

Thank you, Lee Mac ，d2010 and ribarm
I want to write binary files directly.
The write-long function exists, but LSP cannot call it directly.
 I'm trying to make it work.

[baitang36]

Or  How to write directly ?
(Setq dectoint 0xFFAFEAD)
(Setq LeeMac (+ 0xFFAFEAD 0x1FAFEAD))
(Alert "Can you user hexadecimals without convert Dec2Int?")
 

(write-line (itoa 943208504) aa)
Or, for integers greater than 2,147,483,647 (2³¹ - 1):
(write-line (rtos 943208504 2 0) aa)

My experiment is only half successful, and I can realize this idea in FAS. But LSP cannot be implemented。
Please see the attachment

[roy_043]

In BricsCAD this works;

Code - Auto/Visual Lisp: [Select]

1. (defun tt ()
2.   (setq aa (open "d:/tt.bin" "wb"))
3.   (vle-write-int32-be aa 943208504)
4.   (close aa)
5. )

Note the "wb" mode means "write binary" and is undocumented but supported by AutoLISP as well apparently.

In AutoCAD it should be possible to split the 32bit integer into 4 bytes and then write these.
http://www.theswamp.org/index.php?topic=17465.0
http://www.theswamp.org/index.php?topic=41802.10

[d2010]

My experiment is only half successful, and I can realize this idea in FAS. But LSP cannot be implemented。
Please see the attachment

For my Source/s is okay. Thank you,Lee Mac for your-answer.

[baitang36]

In BricsCAD this works;

Code - Auto/Visual Lisp: [Select]

1. (defun tt ()
2.   (setq aa (open "d:/tt.bin" "wb"))
3.   (vle-write-int32-be aa 943208504)
4.   (close aa)
5. )

Note the "wb" mode means "write binary" and is undocumented but supported by AutoLISP as well apparently.

In AutoCAD it should be possible to split the 32bit integer into 4 bytes and then write these.
http://www.theswamp.org/index.php?topic=17465.0
http://www.theswamp.org/index.php?topic=41802.10

thank you

[BIGAL]

Maybe this https://www.cadtutor.net/forum/topic/29079-readwrite-binary-files/