Clarification about -auto_charset pitfalls

This commit is contained in:
Thomas Schmitt 2009-03-22 08:59:18 +00:00
parent b4332a8387
commit bc1453ad0e

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@ -2,7 +2,7 @@
.\" First parameter, NAME, should be all caps .\" First parameter, NAME, should be all caps
.\" Second parameter, SECTION, should be 1-8, maybe w/ subsection .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
.\" other parameters are allowed: see man(7), man(1) .\" other parameters are allowed: see man(7), man(1)
.TH XORRISO 1 "Mar 20, 2009" .TH XORRISO 1 "Mar 21, 2009"
.\" Please adjust this date whenever revising the manpage. .\" Please adjust this date whenever revising the manpage.
.\" .\"
.\" Some roff macros, for reference: .\" Some roff macros, for reference:
@ -658,14 +658,15 @@ When loading the written image after -commit the setting of -out_charset
will be copied to -in_charset. will be copied to -in_charset.
.TP .TP
\fB\-auto_charset\fR "on"|"off" \fB\-auto_charset\fR "on"|"off"
Enable or disable recording of the output character set name in an xattr Enable or disable recording and interpretation of the output character
attribute of the image root directory. If enabled then use an eventual set name in an xattr attribute of the image root directory. If enabled then
recorded character set name as input character set when reading an image. an eventual recorded character set name gets used as input character set
when reading an image.
.br .br
Note that the default output charset is the local character set of the Note that the default output charset is the local character set of the
terminal where xorriso runs. Before attributing this one to the produced terminal where xorriso runs. Before attributing this local character set
ISO image, it is necessary to check whether the terminal properly displays to the produced ISO image, check whether the terminal properly displays
all intended filenames. Check especially the exotic national characters. all intended filenames, especially exotic national characters.
.TP .TP
\fB\-acl\fR "on"|"off" \fB\-acl\fR "on"|"off"
Enable or disable processing of ACLs. Enable or disable processing of ACLs.
@ -1840,7 +1841,7 @@ missing.
.PP .PP
File names are strings of non-zero bytes with 8 bit each. Unfortunately File names are strings of non-zero bytes with 8 bit each. Unfortunately
the same byte string may appear as different peculiar national characters the same byte string may appear as different peculiar national characters
on differently nationalized computers. on differently nationalized terminals.
The meanings of byte codes are defined in \fBcharacter sets\fR which have The meanings of byte codes are defined in \fBcharacter sets\fR which have
names. Shell command iconv -l lists them. names. Shell command iconv -l lists them.
.br .br
@ -1861,6 +1862,23 @@ local character set. xorriso can inquire the same info as shell command
"locale" with argument "charmap". This may be influenced by environment "locale" with argument "charmap". This may be influenced by environment
variables LC_ALL, LC_CTYPE, or LANG and should match the expectations of variables LC_ALL, LC_CTYPE, or LANG and should match the expectations of
the terminal. the terminal.
.br
The default output charset is the local character set of the terminal where
xorriso runs. So by default no conversion happens between local filesystem
names and emerging names in the image. The situation stays ambigous and the
reader has to riddle what character set was used.
.br
By option -auto_charset it is possible to attribute the output charset name
to the image. This makes the situation unambigous. But if your terminal
character set does not match the character set of the local file names,
then this attribute can become plainly wrong and cause problems at read time.
To prevent this it is necessary to check whether the terminal properly
displays all intended filenames. Check especially the exotic national
characters.
.br
To enforce recording of a particular character set name without any conversion
at image generation time, set -charset and -local_charset to the desired name,
and enable -backslash_codes to avoid evil character display on your terminal.
.TP .TP
\fB\-charset\fR character_set_name \fB\-charset\fR character_set_name
Set the character set from which to convert file names when loading an Set the character set from which to convert file names when loading an