Hi Pádraig,
> The following shows I think that iconv is bypassing stdio and buffering
> internally?
>
> (echo; sleep 3; echo) | ltrace iconv -f ASCII
Indeed, the glibc 'iconv' does not use stdio apparently:
__libc_start_main(0x402a00, 3, 0x7fff76b92d68, 0x409c90, 0x409c80 <unfinished
...>
setlocale(6, "")
= "de_DE.UTF-8"
textdomain("libc")
= "libc"
argp_parse(0x60d2e0, 3, 0x7fff76b92d68, 0, 0x7fff76b92c5c)
= 0
strchr("ASCII", '/')
= NULL
strchr("", '/')
= NULL
iconv_open(0x409daf, 0x7fff76b946e6, 0, 0x53494c4300494900, 0xfefefefefefefeff)
= 0x613080
fileno(0x7f4c6e9726a0)
= 0
realloc(NULL, 32768)
= 0x00615100
read(0, "\n", 32768)
= 1
read(0, "\n", 32767)
= 1
read(0, "", 32766)
= 0
iconv(0x613080, 0x7fff76b8ab38, 0x7fff76b8ab30, 0x7fff76b92b48, 0x7fff76b92b40)
= 0
...
> The stdbuf man page notes that:
>
> NOTE: If COMMAND adjusts the buffering of its standard streams (`tee'
> does for e.g.) then that will override corresponding settings changed
> by `stdbuf'. Also some filters (like `dd' and `cat' etc.) don't use
> streams for I/O, and are thus unaffected by `stdbuf' settings.
This paragraph is written in a way that does not make the implications
very clear. How about the attached patch, meant to show the restrictions more
prominently?
2011-06-29 Bruno Haible <br...@clisp.org>
* doc/coreutils.texi (stdbuf invocation): Mention the restrictions on
the command more prominently.
--- doc/coreutils.texi.orig Thu Jun 30 01:31:13 2011
+++ doc/coreutils.texi Thu Jun 30 01:30:54 2011
@@ -15398,6 +15398,17 @@
stdbuf @var{option}@dots{} @var{command}
@end example
+@var{command} must start with the name of a program that
+@enumerate
+@item
+uses the ISO C @code{FILE} streams for input/output (note the
+programs @command{dd} and @command{cat} don't do that),
+
+@item
+does not adjust the buffering of its standard streams (note the
+program @command{tee} is not in this category).
+@end enumerate
+
Any additional @var{arg}s are passed as additional arguments to the
@var{command}.
@@ -15446,12 +15457,6 @@
@end table
-NOTE: If @var{command} adjusts the buffering of its standard streams
-(@command{tee} does for e.g.) then that will override corresponding settings
-changed by @command{stdbuf}. Also some filters (like @command{dd} and
-@command{cat} etc.) don't use streams for I/O, and are thus unaffected
-by @command{stdbuf} settings.
-
@cindex exit status of @command{stdbuf}
Exit status:
--
In memoriam José Olaya <http://es.wikipedia.org/wiki/José_Olaya>
