New options -charset, -in_charset, -out_charset

libisoburn/trunk/xorriso/xorriso.1

@@ -555,6 +555,11 @@ until the next -dev or -indev. After the image has been loaded once, the
 setting is valid for -rollback until next -dev or -indev, where it
 will be reset to "auto".
 .TP
+\fB\-in_charset\fR character_set_name
+Set the character set from which to convert file names when loading an
+image. This has eventually to be done before specifying -dev , -indev or
+-rollback. See paragraph "Character sets" for more explanations.
+.TP
 \fB\-rom_toc_scan\fR "on"|"off"[:"emul_on"|"emul_off"]
 Read-only drives do not tell the actual media type but show any media as
 ROM (e.g. as DVD-ROM). The session history of MMC multi-session media might
@@ -1328,7 +1333,7 @@ If enabled by "on", generate Joliet info additional to Rock Ridge info.
 Specify the volume ID. xorriso accepts any text up to 32 characters,
 but according to rarely obeyed specs stricter rules apply:
 .br
-ECMA 119 demands character set [A-Z0-9_]. Like: "IMAGE_23"
+ECMA 119 demands ASCII characters out of [A-Z0-9_]. Like: "IMAGE_23"
 .br
 Joliet allows 16 UCS-2 characters. Like: "Windows name"
 .br
@@ -1348,6 +1353,10 @@ If you insist in -volid "ISOIMAGE", set it again after those commands.
 Set the publisher string to be written with the next -commit. Permissible
 are up to 128 characters.
 .TP
+\fB\-out_charset\fR character_set_name
+Set the character set to which file names get converted when writing an
+image. See paragraph "Character sets" for more explanations.
+.TP
 \fB\-uid\fR uid
 User id to be used for all files when the new ISO tree gets written to media.
 .TP
@@ -1454,7 +1463,7 @@ boot image which is present on the input media.
 Most safe is the default: -boot_image "any" "discard".
 .br
 
-A bootspec is a word of the form name=value and is used describe the
+A bootspec is a word of the form name=value and is used to describe the
 activation of a ISOLINUX boot image by an El Torito record and eventually
 a MBR. The names "dir" and "bin_path" lead to boot image activation.
 .br
@@ -1491,6 +1500,34 @@ write session if not the isohybrid signature is found in the bin_path file.
 Default is "isohybrid=auto" which silently omits the MBR if the signature is
 missing. 
 .TP
+.B Character sets:
+.PP
+File names are strings of non-zero bytes with 8 bit each. Unfortunately
+the same byte string may appear as different peculiar national characters
+on differently nationalized computers.
+The meanings of byte codes are defined in \fBcharacter sets\fR which have
+names. Shell command iconv -l lists them. 
+.br
+Character sets should not matter as long as only alphanumeric characters are
+used for file names or as long as the computer which runs xorriso uses the
+same character set as the computer which wrote the loaded image and those
+computers which shall read the newly emerging ISO image.
+Outside these constraints it may be necessary to let xorriso convert byte
+codes.
+.br
+There is an input conversion from input character set to the local character
+set which applies when an ISO image gets loaded. A conversion from local
+character set to the output character set is performed when a new
+image tree gets written. The sets can be defined independently by options
+-in_charset and -out_charset. Normally one will have both identical, if ever.
+.br
+xorriso expects and uses the local character set for command arguments
+and file name output. Other character sets will only be in effect on media.
+.TP
+\fB\-charset\fR character_set_name
+Set the character set from which to convert file names when loading an
+image and to which to convert when writing an image.
+.TP
 .B Exception processing:
 .PP
 Since the tasks of xorriso are manifold and prone to external influence, there