Colorize zpool status output

If the ZFS_COLOR env variable is set, then use ANSI color
output in zpool status:

- Column headers are bold
- Degraded or offline pools/vdevs are yellow
- Non-zero error counters and faulted vdevs/pools are red
- The 'status:' and 'action:' sections are yellow if they're
  displaying a warning.

This also includes a new 'faketty' function in libtest.shlib that is
compatible with FreeBSD (code provided by @freqlabs).

Reviewed-by: Jorgen Lundman <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Ryan Moeller <[email protected]>
Signed-off-by: Tony Hutter <[email protected]>
Closes #9340 

1 files changed, 6 insertions, 0 deletions

diff --git a/man/man8/zpool.8 b/man/man8/zpool.8
index 4b15785c2..272e4bc1c 100644
--- a/man/man8/zpool.8
+++ b/man/man8/zpool.8
@@ -453,6 +453,12 @@ Cause
 to dump core on exit for the purposes of running
 .Sy ::findleaks .
 .El
+.Bl -tag -width "ZFS_COLOR"
+.It Ev ZFS_COLOR
+Use ANSI color in
+.Nm zpool status
+output.
+.El
 .Bl -tag -width "ZPOOL_IMPORT_PATH"
 .It Ev ZPOOL_IMPORT_PATH
 The search path for devices or files to use with the pool. This is a colon-separated list of directories in which