Say "boot image" where that is what is meant

"Binary" was doing three jobs. It meant an SPBT file that the machine starts
from; it meant whatever the assembler happened to produce, which is now
either that or a loadable program; and it meant a compiled host tool. A word
that means three things means none of them, and the first of the three has a
name already - this project has been calling them boot images for a while
and the manuals had not caught up.

  Where it means an SPBT file       -> boot image
  Where it means either output      -> output
  Where it means a host executable  -> left alone
  Where it means base two           -> left alone

The user facing messages move with it:

  Error: No boot image specified.
  Usage: ./SplitBit [OPTIONS] <boot image>
  Error: This is not a SplitBit boot image.
  Error: This boot image is in format version 2, and this emulator reads 1.
  Successfully wrote SplitBit boot image to "hello.bin".

The assembler's own help was the interesting case. Its -o writes either
format, so "the binary" there was never right - it is "the output" now, and
the message that names the format is the one that says which it wrote.

No recorded output contained the word, so nothing needed re-blessing.
Checked before starting rather than after.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW

Programs/CosmOS/Assembler/Asm.asm

@@ -6,7 +6,8 @@
 ; Loading and running are separate commands in this shell, so the file to assemble is the
 ; argument to run rather than a second name after the program's.
 ;
-; Reads assembly source off the disk and writes a binary back to it, with no host involved
+; Reads assembly source off the disk and writes a boot image or a loadable program back to it,
+; with no host involved
 ; anywhere. The output has to be byte for byte what the C assembler produces from the same
 ; source, which is the only honest test of it and the one the suite runs.
 ;
@@ -2046,7 +2047,7 @@ ImgHold:
 DropWalk:
   0x00 0x00
 
-; How big a binary this can build. Everything the assembler makes has to fit here at once,
+; How big an output file this can build. Everything the assembler makes has to fit here at once,
 ; because a file is written in one call and there is nowhere to put half of one. CosmOS
 ; itself comes to 9,564 bytes.
 ImgRoom:
@@ -2152,7 +2153,7 @@ BasesText:
 at zero, on top of whatever is there. Give both a #Base, or neither.
 "
 TooBigText:
-"the binary would be bigger than this assembler has room to build
+"the output would be bigger than this assembler has room to build
 "
 NoWriteText:
 "it would not write "

Programs/CosmOS/Assembler/scratch.asm

@@ -17,7 +17,7 @@
 ;
 ;   0x8000  3072   the label index, 768 entries of four
 ;   0x8C00  8192   the label names, packed end to end
-;   0xAC00 13312   the binary being built
+;   0xAC00 13312   the output file being built
 ;   0xE000  1792   the vector names, 64 entries of twenty eight
 ;   0xE700  1758   the reader's stack, six levels of 293
 ;   0xEE00   368   which files have been included, sixteen names of 23

README.md

@@ -2,7 +2,7 @@
 
 SplitBit is an 8 bit computer that does not exist: a CPU with its own instruction set, split Program and Data memories, an interrupt and vector system, a bus that programs can enumerate, a memory controller that can write code into memory, and a disk. This repository is a C implementation of the machine, an assembler for it, a tool for its disks, and the software that runs on it, which now includes an operating system and an assembler written in SplitBit's own assembly language.
 
-**SplitBit assembles SplitBit.** `Programs/CosmOS/Assembler/` runs on the machine, reads source off a SplitBit disk, and writes a binary back to it with no host involved. It builds the operating system it is running under, and it builds itself, both byte for byte identical to what the C assembler produces from the same source. The test suite then boots the CosmOS that CosmOS built and has *that* one assemble CosmOS again, and the second generation is identical to the first, so the machinery has been through itself. After that the host is a convenience rather than a necessity.
+**SplitBit assembles SplitBit.** `Programs/CosmOS/Assembler/` runs on the machine, reads source off a SplitBit disk, and writes a boot image or a loadable program back to it with no host involved. It builds the operating system it is running under, and it builds itself, both byte for byte identical to what the C assembler produces from the same source. The test suite then boots the CosmOS that CosmOS built and has *that* one assemble CosmOS again, and the second generation is identical to the first, so the machinery has been through itself. After that the host is a convenience rather than a necessity.
 
 ```
 > load Asm.sbx
@@ -74,7 +74,7 @@ Then `dir` to see what is there, `load Snake.sbx` and `run` to play something, o
 ## Running Programs: SplitBit
 
 ```
-./SplitBit [options] [binary file]
+./SplitBit [options] [boot image]
 ```
 
 | Option | What it does |
@@ -96,12 +96,12 @@ If the CPU reads a byte that is not an instruction, it goes to the fault handler
 
 | Option | What it does |
 | --- | --- |
-| `-o <file>` | Write the binary to this path. |
+| `-o <file>` | Write the output to this path. |
 | `-I <dir>` | Look in this directory for included files. May be given more than once. |
-| `-M <file>` | Write out which source files the binary depends on, as a make rule. |
+| `-M <file>` | Write out which source files the output depends on, as a make rule. |
 | `-h`, `--help` | Show help and usage information. |
 
-Without `-o` the binary takes the source file's name with a `.bin` extension, in the directory you called the assembler from. Included files are looked for beside the file that includes them, and then along the directories given with `-I`.
+Without `-o` the output takes the source file's name with a `.bin` extension, in the directory you called the assembler from. Included files are looked for beside the file that includes them, and then along the directories given with `-I`.
 
 ## Managing Disks: SplitDisk
 
@@ -123,7 +123,7 @@ Files are laid down contiguously, so a disk can have free blocks without having
 
 ## Building Programs With Make:
 
-The assembler is built to work with make. `-o` puts the binary where the build system wants it, and `-M` writes out which libraries went into it, so that editing a library reassembles everything that includes it.
+The assembler is built to work with make. `-o` puts the output where the build system wants it, and `-M` writes out which libraries went into it, so that editing a library reassembles everything that includes it.
 
 `Programs/makefile` does this for the programs in this repository:
 

Source/Assembler/Assembler.c

@@ -91,13 +91,13 @@ void printUsage(const char *programName) {
     printf("Usage: %s [OPTIONS] <sourcefile>\n", programName);
     printf("\n");
     printf("Options:\n");
-    printf("  -o <file>    Write the binary to this path instead of alongside the source.\n");
+    printf("  -o <file>    Write the output to this path instead of alongside the source.\n");
     printf("  -I <dir>     Look in this directory for included files. May be given more than once.\n");
-    printf("  -M <file>    Write the source files this binary depends on, as a make rule.\n");
+    printf("  -M <file>    Write the source files this output depends on, as a make rule.\n");
     printf("  -h, --help   Display this help message.\n");
 }
 
-// Writes a make rule naming every source file that went into the binary, so that a
+// Writes a make rule naming every source file that went into the output, so that a
 // build system knows to reassemble when any of them changes. The empty rules after it
 // are so that deleting a library does not leave make with a prerequisite it cannot
 // build; without them the build stops instead of just reassembling.

Source/Assembler/assembly.h

@@ -8,13 +8,13 @@
 #ifndef ASSEMBLY_H
 #define ASSEMBLY_H
 
-// ---- The SplitBit binary format ----
+// ---- The SplitBit boot image format ----
 //
-// A binary starts with a file header, then the Program Segment, then the Data
+// A boot image starts with a file header, then the Program Segment, then the Data
 // Segment. All multi byte numbers are stored most significant byte first.
 //
 //   Offset  Size  Field
-//   0       4     "SPBT", so a file that is not a SplitBit binary is spotted at once
+//   0       4     "SPBT", so a file that is not a boot image is spotted at once
 //   4       1     Format version
 //   5       4     Required feature flags
 //   9       3     "PRG"
@@ -27,14 +27,14 @@
 //   ..      2     Vector Segment length, in bytes
 //   ..      K     Vector Segment, four bytes per entry
 //
-// The Vector Segment is optional and comes last, so a binary written before it existed
+// The Vector Segment is optional and comes last, so an image written before it existed
 // simply ends after its Data Segment and still loads. Each entry is two bytes saying
 // where in Program Memory the vector sits, then two bytes saying where its handler is,
 // most significant byte first. It is a list rather than an image of the table, so a
 // program with three handlers costs twelve bytes instead of a padded kilobyte.
 //
-// The feature flags are how a binary says it needs something the base machine does
+// The feature flags are how a boot image says it needs something the base machine does
-// not provide, so that an emulator which cannot provide it refuses to run the binary
+// not provide, so that an emulator which cannot provide it refuses to run the image
 // rather than quietly doing the wrong thing. No features are defined yet; the field
 // is here so that adding one later does not need another format version.
 
@@ -110,7 +110,7 @@
 #define SPLITBIT_HEADER_BYTES (SPLITBIT_MAGIC_LENGTH + 1 + SPLITBIT_FLAGS_LENGTH \
                                + 2 * (SEGMENT_MARKER_LENGTH + SEGMENT_LENGTH_BYTES))
 
-// Features this build of the emulator can provide. A binary asking for anything
+// Features this build of the emulator can provide. An image asking for anything
 // outside this set is refused.
 #define SPLITBIT_FEATURES_SUPPORTED 0x00000000u
 

Source/Assembler/secondPass.c

@@ -653,7 +653,7 @@ void writeOutputFile(const char *outputFileName, uint8_t *Program, int programCo
     }
 
     // Write the file header: the magic, the format version, and the features this
-    // binary needs from the machine. An emulator that cannot provide one of those
+    // boot image needs from the machine. An emulator that cannot provide one of those
     // features refuses the file rather than running it and going quietly wrong.
     fwrite(SPLITBIT_MAGIC, sizeof(char), SPLITBIT_MAGIC_LENGTH, outputFile);
     fputc(SPLITBIT_FORMAT_VERSION, outputFile);
@@ -703,7 +703,7 @@ void writeOutputFile(const char *outputFileName, uint8_t *Program, int programCo
     }
 
     // The Vector Segment, only if the program named any. Leaving it out entirely is
-    // what lets a binary written before vectors existed still load: the reader treats
+    // what lets an image written before vectors existed still load: the reader treats
     // the end of the file as an empty table rather than a missing one.
     int installed = 0;
     for (int i = 0; i < vectorArrayCount; i++) {
@@ -730,7 +730,7 @@ void writeOutputFile(const char *outputFileName, uint8_t *Program, int programCo
     }
 
     fclose(outputFile);
-    printf("Successfully wrote SplitBit binary to \"%s\".\n", outputFileName);
+    printf("Successfully wrote SplitBit boot image to \"%s\".\n", outputFileName);
     printf(GREEN "  Program Segment size: %d bytes.\n  Data Segment size: %d bytes.\n" RESET, programCount, dataCount);
     if (installed > 0) {
         printf(GREEN "  Vectors: %d.\n" RESET, installed);

Source/DiskTool/sbfs.h

@@ -8,7 +8,7 @@
 // has to change there in the same breath.
 //
 // All multi byte numbers are most significant byte first, the same as every other number
-// SplitBit stores: addresses, the SPBT binary header, and the vector table.
+// SplitBit stores: addresses, the SPBT boot image header, and the vector table.
 //
 // Written by Anachronaut
 

Source/Emulator/bootstrap.c

@@ -4,7 +4,7 @@
 // 10/16/2024
 
 #include "bootstrap.h"
-#include "../Assembler/assembly.h" // For the binary format, which both tools share.
+#include "../Assembler/assembly.h" // For the boot image format, which both tools share.
 #include <stdio.h>
 #include <string.h>
 
@@ -39,14 +39,14 @@ static uint8_t readMarker(FILE *file, const char *expected, int length, char *fo
     return strncmp(found, expected, length) != 0;
 }
 
-// Reads the file header: the magic, the format version, and the features the binary
+// Reads the file header: the magic, the format version, and the features the boot image
 // says it needs from the machine.
 static uint8_t readFileHeader(FILE *file) {
     char magic[SPLITBIT_MAGIC_LENGTH + 1];
     if (readMarker(file, SPLITBIT_MAGIC, SPLITBIT_MAGIC_LENGTH, magic)) {
-        fprintf(stderr, "Error: This is not a SplitBit binary.\n");
+        fprintf(stderr, "Error: This is not a SplitBit boot image.\n");
         if (strncmp(magic, "PRG", 3) == 0) {
-            fprintf(stderr, " It looks like a binary from before the format carried a version.\n Reassemble it and try again.\n");
+            fprintf(stderr, " It looks like a boot image from before the format carried a version.\n Reassemble it and try again.\n");
         } else {
             fprintf(stderr, " Expected the file to begin with \"%s\", found \"%s\".\n", SPLITBIT_MAGIC, magic);
         }
@@ -58,7 +58,7 @@ static uint8_t readFileHeader(FILE *file) {
         return 1;
     }
     if (version != SPLITBIT_FORMAT_VERSION) {
-        fprintf(stderr, "Error: This binary is in format version %u, and this emulator reads version %u.\n", version, SPLITBIT_FORMAT_VERSION);
+        fprintf(stderr, "Error: This boot image is in format version %u, and this emulator reads version %u.\n", version, SPLITBIT_FORMAT_VERSION);
         return 1;
     }
 
@@ -68,7 +68,7 @@ static uint8_t readFileHeader(FILE *file) {
     }
     uint32_t missing = required & ~(uint32_t)SPLITBIT_FEATURES_SUPPORTED;
     if (missing) {
-        fprintf(stderr, "Error: This binary was built for a machine this emulator cannot provide.\n");
+        fprintf(stderr, "Error: This boot image was built for a machine this emulator cannot provide.\n");
         fprintf(stderr, " It asks for feature bits 0x%08X, which are not implemented here.\n", missing);
         return 1;
     }
@@ -135,7 +135,7 @@ static uint8_t readVectorSegment(FILE *file, uint8_t *Program) {
             return 1;
         }
         if (slot < SOFTWARE_VECTOR_BASE) {
-            fprintf(stderr, "Error: This binary puts a vector at 0x%04X, which is below the vector table.\n", slot);
+            fprintf(stderr, "Error: This boot image puts a vector at 0x%04X, which is below the vector table.\n", slot);
             return 1;
         }
         Program[slot] = (handler >> 8) & 0xFF;

Source/Emulator/cpu.c

@@ -10,7 +10,7 @@
 uint16_t shiftRegister;
 
 // Reads one entry out of a vector table. Most significant byte first, matching the
-// branch instructions and the binary format.
+// branch instructions and both file formats.
 static uint16_t readVector(const uint8_t *programMemory, uint16_t base, uint8_t index) {
     uint16_t address = base + (uint16_t)index * VECTOR_ENTRY_BYTES;
     return ((uint16_t)programMemory[address] << 8) | (uint16_t)programMemory[address + 1];

Source/Emulator/emulator.c

@@ -79,7 +79,7 @@ int main (int argc, char *argv[]) {
         programFile = argv[optind];
         optind++;
     } else {
-        fprintf(stderr, "Error: No binary file specified.\n");
+        fprintf(stderr, "Error: No boot image specified.\n");
         printHelp(argv[0]);
         return 1;
     }

Source/Emulator/utility.c

@@ -11,7 +11,7 @@
 #include "../Assembler/assembly.h"
 
 void printHelp(const char *programName) {
-    printf("Usage: %s [OPTIONS] <binaryfile>\n", programName);
+    printf("Usage: %s [OPTIONS] <boot image>\n", programName);
     printf("\n");
     printf("Options:\n");
     printf("  -d, --debug       Enable debug mode.\n");

SplitBit Assembler Manual.md

@@ -417,16 +417,16 @@ Assembler [options] <sourcefile>
 
 | Option | Meaning |
 | -- | -- |
-| -o, --output \<file\> | Write the binary to this path. Without it, the binary is named after the source file, with a .bin extension, in the directory the assembler was run from. |
+| -o, --output \<file\> | Write the output to this path. Without it, the output is named after the source file, with a .bin extension, in the directory the assembler was run from. |
 | -I, --include \<dir\> | Look in this directory for included files. May be given more than once, and the directories are searched in the order given. |
-| -M, --depend \<file\> | Write out which source files went into the binary, as a make rule. |
+| -M, --depend \<file\> | Write out which source files went into the output, as a make rule. |
 | -h, --help | Print the options and stop. |
 
-The assembler stops at the first error, says which file and line it was in, and exits without writing a binary.
+The assembler stops at the first error, says which file and line it was in, and exits without writing anything.
 
 ## Building With Make:
 
-The -o and -M options are there so that the assembler fits into a build system. -o puts the binary wherever the build wants it, and -M writes down which libraries went into it, so that editing a library reassembles every program that includes it.
+The -o and -M options are there so that the assembler fits into a build system. -o puts the output wherever the build wants it, and -M writes down which libraries went into it, so that editing a library reassembles every program that includes it.
 
 ```
 $(BUILD)/%.bin: %.asm
@@ -589,7 +589,7 @@ wrote hello.bin: program 17, data 14, labels 2
 
 Loading and running are separate commands in CosmOS, so the source file is the argument to `run`.
 
-**Its output must be byte for byte what the host assembler produces from the same source**, and `Tests/native.sh` checks exactly that: it assembles `Programs/Examples/hello.asm` both ways and compares the files, then runs the one the machine built. This is the discipline SplitDisk and `sbfs.asm` already work under - two implementations of one written specification, each one checking the other. "It ran" is not good enough for an assembler, because a binary with a label one byte out runs right up until it jumps into the middle of an instruction.
+**Its output must be byte for byte what the host assembler produces from the same source**, and `Tests/native.sh` checks exactly that: it assembles `Programs/Examples/hello.asm` both ways and compares the files, then runs the one the machine built. This is the discipline SplitDisk and `sbfs.asm` already work under - two implementations of one written specification, each one checking the other. "It ran" is not good enough for an assembler, because a file with a label one byte out runs right up until it jumps into the middle of an instruction.
 
 ### How It Differs Inside:
 
@@ -649,7 +649,7 @@ wrote Asm.sbx: program 7533, data 4099, labels 555
 
 Both come out **byte for byte identical** to what the host assembler builds from the same source. `make run-cosmos` puts every source file on the disk, so this can be done rather than read about.
 
-**The check that matters most is the third one.** A binary that matches could still have been built by an assembler wrong in some way this particular source happens not to exercise. So `Tests/native.sh` boots the CosmOS that CosmOS built and has *that* assemble CosmOS again - and the second generation is identical to the first, down to the cycle count. It is a fixed point, which means the machinery has been through itself.
+**The check that matters most is the third one.** A file that matches could still have been built by an assembler wrong in some way this particular source happens not to exercise. So `Tests/native.sh` boots the CosmOS that CosmOS built and has *that* assemble CosmOS again - and the second generation is identical to the first, down to the cycle count. It is a fixed point, which means the machinery has been through itself.
 
 After that the host is a convenience rather than a necessity.