Basically, it's a conflict between POSIX and ISO C what do to when
input streams are passed to fflush().
POSIX mandates that the seeking-position should be synced, but ISO C
says it's undefined behaviour.
We love POSIX, but the standard-documents specify that in all conflict
cases, ISO C wins, so this breaks with EBADF on BSD's.
musl and glibc follow POSIX behaviour, which makes sense, but involves
numerous portability concerns.
To get around this, we just don't check fflush() and rely on the fact
that no implementation sets ferror on the file-stream in fflush if it
is an input stream, so every issue caught in fflush() is caught later
with ferror() and fclose().
Add a comment to fshut() because this stuff is so complicated, it
took us a day to figure out.
sbase - suckless unix tools
===========================
sbase is a collection of unix tools that are inherently portable
across UNIX and UNIX-like systems.
The following tools are implemented:
'#' -> UTF-8 support, '=' -> Implicit UTF-8 support, '*' -> Finished,
'|' -> Audited, 'o' -> POSIX 2013 compliant, 'x' -> Non-POSIX,
'()' -> Petty flag
UTILITY MISSING FLAGS
------- -------------
=*|o basename .
=*|o cal .
=*|o cat .
=*|o chgrp .
=*|o chmod .
=*|o chown .
=*|x chroot .
=*|o cksum .
=*|o cmp .
#*|x cols .
#*|x col .
=*|o comm .
=*|o cp (-i)
=*|x cron .
#*|o cut .
=*|o date .
=*|o dirname .
=*|o du .
=*|o echo .
=*|o env .
#*|o expand .
#*|o expr .
=*|o false .
= find .
#*|o fold .
=* o grep .
=*|o head .
=*|x hostname .
=*|o kill .
=*|o link .
=*|o ln .
=*|o logger .
=*|o logname .
#* o ls (-C, -k, -m, -p, -s, -x)
=*|x md5sum .
=*|o mkdir .
=*|o mkfifo .
=*|x mktemp .
=*|o mv (-i)
=*|o nice .
#*|o nl .
=*|o nohup .
#*|o paste .
=*|x printenv .
#*|o printf .
=*|o pwd .
=*|x readlink .
=*|o renice .
=*|o rm (-i)
=*|o rmdir .
# sed .
=*|x seq .
=*|x setsid .
=*|x sha1sum .
=*|x sha256sum .
=*|x sha512sum .
=*|o sleep .
sort -d, -f, -i
=*|o split .
=*|x sponge .
#*|o strings .
=*|x sync .
=*|o tail .
=*|x tar .
=*|o tee .
=*|o test .
=*|o time .
=*|o touch .
#*|o tr .
=*|o true .
=*|o tty .
=*|o uname .
#*|o unexpand .
=*|o uniq .
=*|o unlink .
=*|o uudecode .
=*|o uuencode .
#*|o wc .
=*|o xargs (-p)
=*|x yes .
The complement of sbase is ubase[1] which is Linux-specific and
provides all the non-portable tools. Together they are intended to
form a base system similar to busybox but much smaller and suckless.
Building
--------
To build sbase, simply type make. You may have to fiddle with
config.mk depending on your system.
You can also build sbase-box, which generates a single binary
containing all the required tools. You can then symlink the
individual tools to sbase-box or run: make sbase-box-install
Ideally you will want to statically link sbase. If you are on Linux
we recommend using musl-libc[2].
Portability
-----------
sbase has been compiled on a variety of different operating systems,
including Linux, *BSD, OSX, Haiku, Solaris, SCO OpenServer and others.
Various combinations of operating systems and architectures have also
been built.
You can build sbase with gcc, clang, tcc, nwcc and pcc.
[1] http://git.suckless.org/ubase/
[2] http://www.musl-libc.org/
0c470f5563