pread() and pwrite() are in SUSv2, and all targeted Unix systems have them. Previously, we defined pg_pread and pg_pwrite to emulate these function with lseek() on old Unixen. The names with a pg_ prefix were a reminder of a portability hazard: they might change the current file position. That hazard is gone, so we can drop the prefixes. Since the remaining replacement code is Windows-only, move it into src/port/win32p{read,write}.c, and move the declarations into src/include/port/win32_port.h. No need for vestigial HAVE_PREAD, HAVE_PWRITE macros as they were only used for declarations in port.h which have now moved into win32_port.h. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Greg Stark <stark@mit.edu> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com |
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.. | ||
activity | ||
adt | ||
cache | ||
error | ||
fmgr | ||
hash | ||
init | ||
mb | ||
misc | ||
mmgr | ||
resowner | ||
sort | ||
time | ||
.gitignore | ||
Gen_dummy_probes.pl | ||
Gen_dummy_probes.pl.prolog | ||
Gen_dummy_probes.sed | ||
Gen_fmgrtab.pl | ||
Makefile | ||
README.Gen_dummy_probes | ||
errcodes.txt | ||
generate-errcodes.pl | ||
postprocess_dtrace.sed | ||
probes.d |
README.Gen_dummy_probes
# Generating dummy probes If Postgres isn't configured with dtrace enabled, we need to generate dummy probes for the entries in probes.d, that do nothing. This is accomplished in Unix via the sed script `Gen_dummy_probes.sed`. We used to use this in MSVC builds using the perl utility `psed`, which mimicked sed. However, that utility disappeared from Windows perl distributions and so we converted the sed script to a perl script to be used in MSVC builds. We still keep the sed script as the authoritative source for generating these dummy probes because except on Windows perl is not a hard requirement when building from a tarball. So, if you need to change the way dummy probes are generated, first change the sed script, and when it's working generate the perl script. This can be accomplished by using the perl utility s2p. s2p is no longer part of the perl core, so it might not be on your system, but it is available on CPAN and also in many package systems. e.g. on Fedora it can be installed using `cpan App::s2p` or `dnf install perl-App-s2p`. The Makefile contains a recipe for regenerating Gen_dummy_probes.pl, so all you need to do is once you have s2p installed is `make Gen_dummy_probes.pl` Note that in a VPATH build this will generate the file in the vpath tree, not the source tree.