all repos — slstatus @ 7e29da026b31f02c839b40c4dcf7bd87741a5e4a

my build of slstatus (tools.suckless.org/slstatus/) 

fflush(stdout) to print line by line if stdout is not a tty

To reproduce the issue:
	$ slstatus -s | tee

then it would print only when the stdout buffer is full, by block
of multiple lines.

fflush() makes sure the line is printed at every loop iteration
Josuah Demangeon mail@josuah.net
Tue, 08 May 2018 15:13:56 +0200
commit

7e29da026b31f02c839b40c4dcf7bd87741a5e4a

parent

0f7a34fa310737d94a0d46a0286082fdfaf68ca3

1 files changed, 1 insertions(+), 0 deletions(-)

jump to
M slstatus.c → slstatus.c 
@@ -98,6 +98,7 @@ }
 
 		if (sflag) {
 			printf("%s\n", status);
+			fflush(stdout);
 		} else {
 			XStoreName(dpy, DefaultRootWindow(dpy), status);
 			XSync(dpy, False);