Add code

LICENSE

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+MIT License
+
+Copyright (c) 2021 Alinur Songül
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

Makefile

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+all=midmesg
+
+CC=gcc
+CFLAGS=-Wall -Wextra -o midmesg
+
+midmesg: midmesg.c
+	$(CC) midmesg.c $(CFLAGS)
+
+install:
+	cp midmesg /usr/local/bin/
+
+uninstall:
+	rm -f /usr/local/bin/midmesg
+
+clean:
+	rm -f midmesg

README.md

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+# midmesg
+**Mi**cro **dmesg** is a lighterweight alternative to dmesg.
+
+## Dependencies
+- **midmesg** should work perfectly fine on both musl libc and glibc.
+- **midmesg** requires header files for your Linux kernel. 
+
+Your Linux distribution should bundle them in a package named `linux-headers` or something similar to that.
+
+## Installation
+After you've cloned the Git repository, use these commands to compile and install **midmesg**.
+```
+make
+doas make install
+```
+
+To uninstall **midmesg**, use `doas make uninstall`.
+
+## Tasks
+- find some way to retain logs
+According to the [klogctl(3)](http://man.he.net/?topic=klogctl&sections=3) man page:
+
+> Bytes read from the log disappear from the log buffer:
+> the information can be read only once.
+
+- use a built-in pager instead of printing logs to the terminal or hoping that `less` exists on the system

midmesg.c

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+/* midmesg - Display Linux kernel log information
+ *
+ * MIT License
+ *
+ * Copyright (c) 2021 Alinur Songül
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+#include <sys/klog.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <stdarg.h>
+
+#define PROGRAM "midmesg"
+
+#define eprintf(...) fprintf(stderr, __VA_ARGS__)
+
+int main()
+{
+	int kbuf_unread_size;
+
+	/* Get the number of all unread bytes in
+	 * the kernel ring buffer */
+	kbuf_unread_size = klogctl(9, NULL, 0);
+
+	if (kbuf_unread_size < 0)
+	{
+		eprintf("%s: unable to read log buffer: %s\n",
+			PROGRAM, strerror(errno));
+		exit(errno);
+	}
+
+
+	/* allocate memory for kernel log to be stored in memory */
+	char* kbuf = (char*)malloc(kbuf_unread_size);
+
+	printf("Waiting for klogctl...");
+	int read_bytes = klogctl(2, kbuf, kbuf_unread_size);
+
+	if (read_bytes != -1)
+		printf("Read %d bytes\n\n", read_bytes);
+	else {
+		eprintf("%s\n", strerror(errno));
+		free(kbuf); /* free up leftover allocated memory  */
+		exit(errno);
+	}
+	
+	printf("%s\n", kbuf);
+	free(kbuf);
+
+
+	return 0;
+}