make default socket path include $DISPLAY

for easier Xephyr handling & stuff

README.md

@@ -5,7 +5,7 @@
 ## Usage
 Hotkeys are case-insensitive, with this syntax: `modifier1-modifier2-...-key`. For more info on this, check [this link](https://pkg.go.dev/github.com/alex11br/xgbutil@v0.0.0-20211225011412-f2944427ac98/keybind#hdr-Key_sequence_format) of the underlaying library. Note that, for this moment, controling for the lock (Caps Lock) and the mod2 (Num Lock) modifiers isn't allowed.
 
-The app uses by default some config files: `/etc/gxhkrc` and `$XDG_CONFIG_HOME/gxhk/gxhkrc`. Using the `-C` flag, they can be ignored, and with the `-c` flag, new ones can be specified. Using the `-s` flag, a different socket besides the default `/tmp/gxhk.sock` can be specified.
+The app uses by default some config files: `/etc/gxhkrc` and `$XDG_CONFIG_HOME/gxhk/gxhkrc`. Using the `-C` flag, they can be ignored, and with the `-c` flag, new ones can be specified. Using the `-s` flag, a different socket besides the default `/tmp/gxhk$DISPLAY.sock` can be specified.
 
 Here are some examples:
 ```sh

common/args.go

@@ -1,6 +1,11 @@
 package common
 
-import "github.com/alexflint/go-arg"
+import (
+	"fmt"
+	"os"
+
+	"github.com/alexflint/go-arg"
+)
 
 type BindCmd struct {
 	Released    bool   `arg:"-r" help:"bind the HOTKEY on its release instead of its press"`
@@ -19,7 +24,7 @@ type InfoCmd struct {
 }
 
 type Args struct {
-	SocketPath       string   `arg:"-s,--socket" help:"use the given SOCKET file" default:"/tmp/gxhk.sock" json:"-"`
+	SocketPath       string   `arg:"-s,--socket" help:"use the given SOCKET file instead of the default one" json:"-"`
 	ConfigFiles      []string `arg:"-c,--config,separate" help:"use the given CONFIG file, besides all the others" json:"-"`
 	NoDefaultConfigs bool     `arg:"-C,--no-default-configs" help:"ignore the default config files" json:"-"`
 
@@ -28,8 +33,16 @@ type Args struct {
 	Info   *InfoCmd   `arg:"subcommand:info" help:"show infos about the bound keys and their commands" json:",omitempty"`
 }
 
+// ParseArgs gives us an Args structure based on the passed command-line flags.
+// If its SocketPath is not set, we'll set it for our convenience to the default value,
+// which must be computed on the spot using the $DISPLAY environment variable.
+// Besides that, the resulting arg.Parser is also returned for our convenience.
 func ParseArgs() (Args, *arg.Parser) {
 	var args Args
 	p := arg.MustParse(&args)
+
+	if args.SocketPath == "" {
+		args.SocketPath = fmt.Sprintf("/tmp/gxhk%s.sock", os.Getenv("DISPLAY"))
+	}
 	return args, p
 }

gxhk.1

@@ -27,7 +27,7 @@ is a hotkey daemon for X, something like \fBsxhkd\fR. What makes it special is t
 Display some help information.
 .TP
 .BR \-s ", " \-\-socket " " \fIpath
-Use \fIpath\fR as the socket path instead of the default \fI/tmp/gxhk.sock\fR.
+Use \fIpath\fR as the socket path instead of the default \fI/tmp/gxhk$DISPLAY.sock\fR.
 
 .SS Daemon-start-only options
 .TP