1 files changed, 27 insertions, 0 deletions
diff --git a/lib/libc/stdio/fputc.c b/lib/libc/stdio/fputc.c
new file mode 100644
index 00000000..c544d5dd
--- /dev/null
+++ b/lib/libc/stdio/fputc.c
@@ -0,0 +1,27 @@
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <io.h>
+
+int fputc(int c, FILE *stream)
+{
+	if (!stream) {
+		errno = EINVAL;
+		return EOF;
+	}
+
+	// Special case for string buffer operations (snprintf)
+	// When fd is -1, we're writing to a string buffer
+	if (stream->fd == -1 && stream->buf != NULL) {
+		// Check if there's space (leave room for null terminator)
+		if (stream->buf_len >= stream->buf_size - 1) {
+			return EOF;
+		}
+
+		stream->buf[stream->buf_len++] = (char)c;
+		return (unsigned char)c;
+	}
+
+	// For regular file operations, use fwrite
+	return fwrite(&c, 1, 1, stream) ? c : EOF;
+}