[dev] [PATCH slstatus] Add a -1 option flag

[Daniel Moch]

Allow slstatus to be used by programs that can grab status by calling
an external program on a periodic basis (e.g. tmux)
---
 slstatus.1 | 5 ++++-
 slstatus.c | 9 ++++++---
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/slstatus.1 b/slstatus.1
index da1a99a..d802037 100644
--- a/slstatus.1
+++ b/slstatus.1
@@ -1,4 +1,4 @@
-.Dd 2017-08-10
+.Dd 2020-06-23
 .Dt SLSTATUS 1
 .Os
 .Sh NAME
@@ -7,6 +7,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl s
+.Op Fl 1
 .Sh DESCRIPTION
 .Nm
 is a suckless status monitor for window managers that use WM_NAME (e.g. dwm) or
@@ -18,6 +19,8 @@ outputs to WM_NAME.
 .Bl -tag -width Ds
 .It Fl s
 Write to stdout instead of WM_NAME.
+.It Fl 1
+Write once to stdout and quit.
 .El
 .Sh CUSTOMIZATION
 .Nm
diff --git a/slstatus.c b/slstatus.c
index 96fa5b6..f1f0741 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -42,7 +42,7 @@ difftimespec(struct timespec *res, struct timespec *a, struct 
timespec *b)
 static void
 usage(void)
 {
-       die("usage: %s [-s]", argv0);
+       die("usage: %s [-s] [-1]", argv0);
 }

 int
@@ -57,6 +57,9 @@ main(int argc, char *argv[])

        sflag = 0;
        ARGBEGIN {
+               case '1':
+                       done = 1;
+                       /* fallthrough */
                case 's':
                        sflag = 1;
                        break;
@@ -77,7 +80,7 @@ main(int argc, char *argv[])
                die("XOpenDisplay: Failed to open display");
        }

-       while (!done) {
+       do {
                if (clock_gettime(CLOCK_MONOTONIC, &start) < 0) {
                        die("clock_gettime:");
                }
@@ -124,7 +127,7 @@ main(int argc, char *argv[])
                                }
                        }
                }
-       }
+       } while (!done);

        if (!sflag) {
                XStoreName(dpy, DefaultRootWindow(dpy), NULL);
--
2.27.0