ftw: default flags to ftw-phys

More often than not, you want the FTW_PHYS flag when
calling the nftw function. Let's make that the default
in TXR's wrapper.

* ftw.c (ftw_wrap): Default to FTW_PHYS when flags
argument not given, rather than zero, subject to
compatibility option.
(ftw_init): Don't check for FTW_PHYS with ifdef, since
we relied on it being present. And anyway, any nftw
implementation must have that.

* txr.1: Documented.

1 files changed, 21 insertions, 1 deletions

diff --git a/txr.1 b/txr.1
index 69b5e903..3f585b29 100644
--- a/txr.1
+++ b/txr.1
@@ -74306,9 +74306,22 @@ and
 arguments are reversed with respect to the C language interface.
 They are both optional;
 .meta flags
-defaults to zero, and
+defaults to the value of
+.code ftw-phys
+and
 .meta nopenfd
 defaults to 20.
+If an argument is given to
+.metn flags ,
+then the presence of the
+.code ftw-phys
+is no longer implied; the flag must be explicitly
+included in the argument in order to be present.
+
+Compatibility Note: the
+.meta flags
+parameter defaults to an argument value of zero in \*(TX
+versions 283 or lower.
 
 The
 .meta path-or-list
@@ -89972,6 +89985,13 @@ of these version values, the described behaviors are provided if
 is given an argument which is equal or lower. For instance
 .code "-C 103"
 selects the behaviors described below for version 105, but not those for 102.
+.IP 283
+In \*(TX 283 and older versions, the
+.meta flags
+parameter of the
+.code ftw
+function defaults to zero, rather than
+.codn ftw-phys .
 .IP 275
 In \*(TX 275 and older versions, the FFI type operator
 .code align