* libguile/filesys.c (scm_sendfile): In Linux-style sendfile(2) code, if
EINTR or EAGAIN occurs, set result to 1 (not 0) so that we actually
keep going. In non-sendfile(2) code, deal gracefully with short reads
due to EOF.
* test-suite/tests/filesys.test ("sendfile"): Use 'let*' to guarantee
the needed order of operations: write (test-file) and then read it.
Add code to check the written data (not just the returned length) in
all tests, including the cases that hit EOF prematurely.
* libguile/filesys.c (scm_sendfile)[HAVE_SYS_SENDFILE_H &&
HAVE_SENDFILE]: Compare RESULT with C_COUNT. Loop until C_COUNT bytes
have been sent.
* doc/ref/posix.texi (File System): Update the description. Explain the
new semantics.
* test-suite/tests/filesys.test ("sendfile"): Rewrite using
`pass-if-equal'. Check the return value for all the tests.
["file with offset past the end", "file with offset near the end"]:
New tests.
* configure.ac: Check for <sys/sendfile.h> and `sendfile'.
* libguile/filesys.c (scm_sendfile): New function.
* libguile/filesys.h (scm_sendfile): New declaration.
* test-suite/tests/filesys.test ("sendfile"): New test prefix.
* doc/ref/posix.texi (File System): Document `sendfile'.
* libguile/ports.h:
* libguile/ports.c (scm_consume_byte_order_mark): New procedure.
* libguile/fports.c (scm_open_file): Call consume-byte-order-mark if we
are opening a file in "r" mode.
* libguile/read.c (scm_i_scan_for_encoding): Don't do anything about
byte-order marks.
* libguile/load.c (scm_primitive_load): Add a note about the duplicate
encoding scan.
* test-suite/tests/filesys.test: Add tests for UTF-8, UTF-16BE, and
UTF-16LE BOM handling.
