* libguile/posix.h:
* libguile/posix.c (scm_utime): Add optional nanosecond arguments. This
is an incompatible change on the C level, but it's unlikely people are
using this POSIX wrapper function, because they would just use the
POSIX function directly. Hopefully, anyway.
* module/system/base/compile.scm (call-with-output-file/atomic):
Propagate source timestamps to targets with nanosecond precision, if
available. Fixes build on systems with ext4 filesystems.
* libguile/filesys.c (scm_stat2scm):
* module/ice-9/posix.scm (stat:atimensec, stat:mtimensec)
(stat:ctimensec): Add three new elements to Scheme stat structures,
for nanosecond-level timestamps.
* configure.ac: Add checks for utimensat, and for nanosecond fields in
struct stat. We should switch to using Gnulib things for these,
though.
* doc/ref/posix.texi (File System): Add documentation for utime's
additional arguments, and nanosecond stat timestamp accessors.
because it looks better in the DVI output. Exceptions are
- wide examples, which would cause overfull hboxes if they
used the bigger @lisp font
- very large examples, which may look too big at the @lisp size.
As the Autoconf documentation says, "These days portable programs
[...] should not rely on `HAVE_RESTARTABLE_SYSCALLS', since nowadays
whether a system call is restartable is a dynamic issue, not a
configuration-time issue."
In other words, if we ever rely on HAVE_RESTARTABLE_SYSCALLS, we are
at the mercy of any code that Guile happens to be linked with, because
that code could install a signal handler without the SA_RESTART flag,
and then a Guile system call could unexpectedly return EINTR.
The readline part of this goes back to this problem report:
http://sources.redhat.com/ml/guile/2000-05/msg00177.html; and is an
excellent example of the above paragraph. It was noted during the
discussion that undefining HAVE_RESTARTABLE_SYSCALLS would fix the
problem, but that solution wasn't adopted - I guess because Guile was
still using cooperative threads then (not pthreads) and so there was a
significant concern (whether founded or not) that not using
restartable syscalls (where available) could lead to a loss of
performance.
Now Guile's default mode of operation is with pthreads, where we
already don't assume that HAVE_RESTARTABLE_SYSCALLS is reliable, so
there is no possible further performance loss. And in any case we
really have no choice, if we want correct operation.
Thanks to Sylvain Beucler for reporting this and suggesting the fix.
* configure.in (AC_SYS_RESTARTABLE_SYSCALLS): Removed.
* doc/ref/posix.texi (Signals): Remove statement that Guile always
sets SA_RESTART flag.
* guile-readline/configure.in (GUILE_SIGWINCH_SA_RESTART_CLEARED):
Remove this setting, together with its test code.
(HAVE_RL_PRE_INPUT_HOOK): Remove this setting and its code, as no
longer needed.
* guile-readline/readline.c (sigwinch_enable_restart): Removed.
(scm_init_readline): Remove setting of rl_pre_input_hook.
* libguile/_scm.h (SCM_SYSCALL): Remove the definition that relies on
HAVE_RESTARTABLE_SYSCALLS.
* libguile/scmsigs.c (scm_sigaction_for_thread): Don't always set the
SA_RESTART flag if available. Update docstring accordingly.
(scm_init_scmsigs): Remove code that sets SA_RESTART flag for all
signals.
* THANKS: Add Sylvain.
(Network Socket Address): New section, move sockaddr bits to here, add
new make-socket-address.
(Network Sockets and Communication): In connect, bind, and sendto, now
take socket address object. In bind, leave INADDR constants for
"Network Address Conversion" node. In those plus accept, getsockname,
getpeername, reword a bit for clarity.
(File System): In access?, reword a bit, clarify real
versus effective ID handling, cross reference glibc on that, and
recommend against access tests in library functions.
