first commit! 🎉

.gitignore

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+.DS_Store
+axd
+*.o

Makefile

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+CC = clang
+CFLAGS = -O2
+TARGET_EXEC = axd
+
+build: axd.c.o
+	$(CC) $(CFLAGS) -o $(TARGET_EXEC) axd.c.o
+
+%.c.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+install: $(TARGET_EXEC)
+	cp $(TARGET_EXEC) /usr/local/bin/
+	chmod +x /usr/local/bin/$(TARGET_EXEC)
+
+clean:
+	rm axd axd.c.o

README.md

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+# axd
+
+Simple recreation of `xxd` from scratch!
+
+Built purely for learning; I don't expect to pack this with features by any means.
+
+## Usage
+
+```sh
+axd <file>
+```
+
+## Build
+
+**Requirements:**
+- a computer
+- `clang`
+
+`make build` will build the binary, and `sudo make install` will install it to `/usr/local/bin` with execute permissions.
+If you're on Windows, I'm so sorry!

axd.c

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+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+    if (argc != 2) {
+        printf("Usage: %s <file>\n", argv[0]);
+        return 1;
+    }
+
+    FILE *file = fopen(argv[1], "r");
+
+    if (file == NULL) {
+        fprintf(stderr, "Failed to open file: %s\n", strerror(errno));
+        return 1;
+    }
+
+    fseek(file, 0, SEEK_END);
+    size_t filesize = ftell(file);
+    fseek(file, 0, 0);
+
+    char buffer[filesize + 1];
+    fread(buffer, 1, filesize, file);
+    buffer[filesize] = '\0';
+
+    static int width = 0x10;
+    size_t offset = 0;
+    while (offset < filesize) {
+        printf("%08lx: ", offset);
+
+        // print hex chars
+        for (int c = 0; c < 0x10; c++) {
+            if (offset + c >= filesize)
+                printf("  ");
+            else {
+                if ((buffer[offset + c] & 0xff) < 0x10)
+                    printf("0");
+                printf("%x", buffer[offset + c] & 0xff);
+            }
+            
+            if (c % 2 != 0)
+                printf(" ");
+        }
+
+        printf(" ");
+
+        // print ASCII chars
+        for (int o = 0; o < 0x10 && offset + o < filesize; o++) {
+            char c = buffer[offset + o];
+            if (c > 31)
+                printf("%c", c);
+            else
+                printf(".");
+        }
+
+        printf("\n");
+        offset += 0x10;
+    }
+
+    return 0;
+}