Fixed an error on compilation and better described set up.

Makefile

@@ -1,7 +1,7 @@
 .POSIX:
 .PHONY: all clean splitters
 
-CFLAGS := -Wall -Werror $(shell pkg-config --cflags vtk) -D_POSIX_C_SOURCE=200809L
+CFLAGS := -Wall $(shell pkg-config --cflags vtk) $(shell pkg-config --cflags cairo-xlib) -D_POSIX_C_SOURCE=200809L
 LDFLAGS := $(shell pkg-config --libs vtk) -lpthread
 
 SPLITTER_FLAGS := -D_POSIX_C_SOURCE=200809L

README.md

@@ -73,3 +73,13 @@ requires ptrace privileges to work, as it must read Portal 2's memory.
 These can be given by running the following command as root:
 
 	setcap cap_sys_ptrace=eip ./splitter
+
+## Set up
+
+To set up adrift you need to create a configuration directory. The directory can have any name, but the name "portal2" or the category of the speedrun. The directory should contain the files below 
+- splits 
+- splitter
+
+To create the splits file you can read the 'Usage' section of this Readme.
+
+If you compiled adrift, your splitter file will be in ./splitters/sar_split, rename it to splitter and move it to the directory.

main.c

@@ -122,6 +122,7 @@ int main(int argc, char **argv) {
 	ssize_t nsplits = read_splits_file("splits", &splits);
 
 	if (nsplits == -1) {
+		fputs("Error: Missing a splits file.\n", stderr);
 		return 1;
 	}