Tachikoma
a15e172c2a
Bumps all three ak* submodules to their current main, applies what their
upgrade notes require, and retires the two workarounds they make obsolete.
libakerror 2.0.1 -> 2.0.2 (63 commits). Two of its fixes were this
repository's own filed issues, and both workarounds are gone:
- It namespaces its embedded `coverage` target now, the same
CMAKE_SOURCE_DIR test it already applied to `mutation` (its issue #15).
The add_custom_target() shadow that renamed it on the way past could
only ever fire on a name the dependency has stopped using, so it is
deleted rather than left as dead code.
- It installs akerrorConfigVersion.cmake at SameMajorVersion (its issue
#16). MAINTENANCE.md said to add a `1.0` floor to our find_dependency
calls when this landed; the floor is now `2.0`, and we have no
find_dependency calls to add it to, so the paragraph says that instead
of an instruction nobody can follow.
Its IGNORE context also changed shape: `__akerr_last_ignored` was an extern
pointer, and is now a per-translation-unit `static akerr_last_ignored` holding
a copy, so the pool slot can be released. Nothing here referenced the symbol,
but it costs us 1.35 MiB of thread-local storage -- 38 TUs x 37,296 bytes,
measured as the entire TLS segment of build/basic, where 2.0.1 produced no TLS
segment at all -- plus 84 -Wunused-variable warnings. Filed upstream as
libakerror issue #37 and recorded in MAINTENANCE.md rather than patched here,
because patching a submodule forks it.
libakstdlib gains directory and file-metadata wrappers with no version bump.
aksl_snprintf keeps its `int *count` -- an intermediate commit removed it and
the merge put it back -- but now reports the required length on truncation
rather than 0. Every call site here reads it only after a successful return,
so nothing moved.
The directory wrappers close the gap DIRECTORY was refused for (libakstdlib
issue #10). The verb is still unwritten, so it still refuses, but it no longer
blames a wrapper that exists: the message is "DIRECTORY is not implemented
yet" and tests/disk_verbs.c asserts both that it says so and that it does not
name libakstdlib. What writing it would need is akbasic issue #55.
libakgl moves to the current main at 0.9.0. It registers libccd and tg as
submodules, so a tree that only ran `git submodule update --init --recursive`
before the bump needs it again or the configure fails on a missing
libccd/src/ccd/config.h.cmake.in.
Verified: 114/114 default, 116/116 under -DAKBASIC_WITH_AKGL=ON, docs_examples
green in both. libakerror's UPGRADING.md documents a 2.0.3 that project()
never stamped, so the version tables read 2.0.2 -- libakerror issue #38.
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
Co-Authored-By: Claude Code (Claude Opus 5, claude-opus-5[1m]) <noreply@anthropic.com>
144 lines
3.9 KiB
Markdown
144 lines
3.9 KiB
Markdown
# 9. Files and disk
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There is no 1541. The disk verbs work against the filesystem where that means
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something, and refuse by name where it does not.
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## Program storage
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```basic repl
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10 PRINT "HI"
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DSAVE "myprogram.bas"
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DLOAD "myprogram.bas"
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VERIFY "myprogram.bas"
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```
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```output
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OK
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```
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`SAVE` and `LOAD` are the same verbs under their other names, and `DVERIFY` is
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`VERIFY`. A program is saved as plain text with its line numbers, so you can edit it in
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anything.
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**`DSAVE` always writes line numbers, including ones you did not.** A program loaded
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from a file that had none is given them
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([Chapter 2](02-getting-started.md#a-program-in-a-file-does-not-need-them)), and those
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are what gets written back. They come out one apart, so there is no room to insert
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between them: `RENUMBER` before `DSAVE` if you want the gaps.
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`VERIFY` compares what is in memory against the file and prints `OK`, or reports how
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many lines differ.
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## Files
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Ten channels, numbered 0 to 9.
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```basic
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10 DOPEN 1, "scores.txt", W
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20 PRINT #1, "ADA 4000"
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30 PRINT #1, "GRACE 3800"
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40 DCLOSE 1
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50 DOPEN 2, "scores.txt"
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60 INPUT #2, LINE$
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70 PRINT LINE$
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80 DCLOSE 2
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```
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```output
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ADA 4000
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```
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| Verb | What it does |
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|---|---|
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| `DOPEN n, "name"` | open for reading |
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| `DOPEN n, "name", W` | open for writing |
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| `APPEND n, "name"` | open for writing at the end |
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| `DCLOSE n` | close one channel |
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| `DCLOSE` | close all of them |
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| `PRINT #n, expr` | write a line |
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| `INPUT #n, VAR` | read a line |
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| `RECORD n, r` | position at record `r` |
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**Note the space before the `#`.** A C128 writes `PRINT#1,A$`; here the `#` has to be
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its own word, because `PRINT#` would otherwise scan as a variable name. See Chapter 13.
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Reading past the end of a file leaves the variable empty rather than raising, so a read
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loop tests what it got:
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```basic setup=textfiles
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10 DOPEN 1, "data.txt"
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20 DO
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30 INPUT #1, L$
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40 IF L$ = "" THEN EXIT
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50 PRINT L$
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60 LOOP
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70 DCLOSE 1
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```
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```output
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ONE
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TWO
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```
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Reading a channel opened for writing — or writing one opened for reading — is refused,
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as is using a channel that is not open.
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`RECORD` counts *lines*, not fixed-length records: a filesystem file has no record
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length to seek by, so it rewinds and reads forward.
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## Managing files
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```basic setup=textfiles
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10 COPY "a.txt", "b.txt"
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20 CONCAT "a.txt", "b.txt"
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30 RENAME "b.txt", "c.txt"
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40 SCRATCH "c.txt"
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```
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`COPY` duplicates, `CONCAT` appends one file to another, `RENAME` moves, `SCRATCH`
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deletes. Deleting a file that is not there is reported rather than ignored.
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## Binary blocks
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```basic
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10 A$ = "BINARY DATA"
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20 B$ = "............"
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30 BSAVE "block.dat", POINTER(A$), POINTER(A$) + 12
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40 BLOAD "block.dat", POINTER(B$), 12
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50 PRINT B$
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```
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```output
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BINARY DATA
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```
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`BSAVE` writes a range of memory and `BLOAD` reads one back. **`BLOAD` requires a
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length**, unlike a C128's, because the address is a real address in this process and a
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file longer than you expected would write past whatever you pointed at. For the same
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reason line 20 is not optional: `POINTER` gives you the address of a string that already
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exists, and reading into one you never sized writes over something else.
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## What is refused, and why
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| Verb | Why not |
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|---|---|
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| `HEADER` | formats a disk. On a filesystem that would have to mean "delete everything here" |
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| `COLLECT` | validates a disk's block allocation map. There is no map |
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| `BACKUP` | duplicates one disk onto another. There are no disks |
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| `BOOT` | loads and runs a boot sector. There is no boot sector |
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| `DIRECTORY` / `CATALOG` | not written yet. It was blocked on a directory-reading wrapper in the standard library; that landed, so only the verb is outstanding |
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`DCLEAR` is the exception among the drive verbs: resetting a drive also closes its
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channels, and closing the channels is real, so that is what it does.
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Each refusal names itself and says why:
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```basic
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10 HEADER "DISK"
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```
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```output
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? 10 : RUNTIME ERROR HEADER formats a disk, and there is no disk drive here -- only a filesystem
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```
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