Unable to open/view JAR archives

[mc-butler]

Important

This issue was migrated from Trac:

Origin	https://midnight-commander.org/ticket/4569
Reporter	alexm (@amorozov)

This is an almost a copy of #4208, some three years later.

System: Manjaro/x64
MC: 4.8.31-3.

On pressing <Enter> on a JAR nothing happens.
On pressing <F3> on s JAR an error message pops up: Cannot open "/path/to/file.jar" in parse mode Operation not supported (95)
Renaming JAR to ZIP solves the problem

LC_MESSAGES=C mc -V

Built with GLib 2.78.4
Built with S-Lang 2.3.3 with terminfo database
Built with libssh2 1.11.0
With builtin Editor and Aspell support
With subshell support as default
With support for background operations
With mouse support on xterm and Linux console
With support for X11 events
With internationalization support
With multiple codepages support
With ext2fs attributes support
Virtual File Systems:
 cpiofs, tarfs, sfs, extfs, ftpfs, sftpfs, shell
Data types:
 char: 8; int: 32; long: 64; void *: 64; size_t: 64; off_t: 64;

LC_MESSAGES=C mc -F

Home directory: /home/alex
Profile root directory: /home/alex

[System data]
    Config directory: /etc/mc/
    Data directory:   /usr/share/mc/
    File extension handlers: /usr/lib/mc/ext.d/
    VFS plugins and scripts: /usr/lib/mc/
        extfs.d:        /usr/lib/mc/extfs.d/
        shell:          /usr/lib/mc/shell/

[User data]
    Config directory: /home/alex/.config/mc/
    Data directory:   /home/alex/.local/share/mc/
        skins:          /home/alex/.local/share/mc/skins/
        extfs.d:        /home/alex/.local/share/mc/extfs.d/
        shell:          /home/alex/.local/share/mc/shell/
        mcedit macros:  /home/alex/.local/share/mc/mc.macros
        mcedit external macros: /home/alex/.local/share/mc/mcedit/macros.d/macro.*
    Cache directory:  /home/alex/.cache/mc/

mc --configure-options

'--prefix=/usr' '--libexecdir=/usr/lib' '--sysconfdir=/etc' '--enable-aspell' '--with-screen=slang' '--with-x' 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions         -Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security         -fstack-clash-protection -fcf-protection -g -ffile-prefix-map=/build/mc/src=/usr/src/debug/mc -flto=auto' 'LDFLAGS=-Wl,-O1 -Wl,--sort-common -Wl,--as-needed -Wl,-z,relro -Wl,-z,now          -Wl,-z,pack-relative-relocs -flto=auto'

file httpcore-4.4.10.jar

httpcore-4.4.10.jar: Java archive data (JAR)

section [jar] of /etc/mc/mc.ext.ini

Type=\(Java\ (Jar\ file|archive)\ data\ \((zip|JAR)\)
TypeIgnoreCase=true
Open=%cd %p/uzip://
View=%view{ascii} /usr/lib/mc/ext.d/archive.sh view zip

[mc-butler]

Changed by andrew_b (@aborodin) on Aug 17, 2024 at 4:15 UTC (comment 1)

• Component changed from mcview to mc-core
• Status changed from new to closed
• Resolution set to invalid
• Milestone Future Releases deleted

Fixed in #4502.

[mc-butler]

Changed by zaytsev (@zyv) on Aug 17, 2024 at 6:47 UTC (comment 2)

Another duplicate in Ubuntu: https://bugs.launchpad.net/ubuntu/+source/mc/+bug/2076503

[rajdikshant]

Unable to open ODS file. Default application is Gnumeric. Same (95) error.

System: Debian 13.1
MC: 4.8.33

[zyv]

Feel free to create a proper bug report, or better yet, investigate what's going on with your mc.ext rules. Problems with escaping that we were aware of were resolved in version 4.8.33.

[rajdikshant]

Created a new report: #4760

[ibm5110]

Problem still persists with 4.8.33:

GNU Midnight Commander 4.8.33
Built with GLib 2.84.4
Built with S-Lang 2.3.3 with terminfo database
Built with libssh2 1.11.1
With builtin editor and aspell support
With subshell support as default
With support for background operations
With mouse support on xterm and Linux console
With support for X11 events
With internationalization support
With multiple codepages support
With ext2fs attributes support
Virtual File Systems:
 cpiofs, tarfs, sfs, extfs, ext2undelfs, ftpfs, sftpfs, shell
Data types:
 char: 8; int: 32; long: 64; void *: 64; size_t: 64; off_t: 64; uintmax_t: 64;

# file Public_Release.jar
Public_Release.jar: Zip archive data, made by v2.0 UNIX, extract using at least v2.0, last modified Dec 05 2025 14:18:12, uncompressed size 0, method=deflate

I always get "Operation not supported (95)" when I try to view the file within mc. Renaming the file to ...zip works.
Heres the section of the mc.ext.ini:

[jar]
Type=\\(Java (Jar file|archive) data \\((zip|JAR)\\)\\)
TypeIgnoreCase=true
Open=%cd %p/uzip://
View=%view{ascii} /usr/lib/mc/ext.d/archive.sh view zip

BTW calling MC_EXT_FILENAME=Public_Release.jar /usr/lib/mc/ext.d/archive.sh view zip does work! So it must be a problem within mc or with the parsing of the output.

[zyv]

BTW calling MC_EXT_FILENAME=Public_Release.jar /usr/lib/mc/ext.d/archive.sh view zip does work! So it must be a problem within mc or with the parsing of the output.

No, obviously the output of file doesn't match the regex. Maybe we should just give up and merge #4862 😢

[ibm5110]

No, obviously the output of file doesn't match the regex.

Is that the case? If file says that it is a ZIP archive, then why doesn't the rule for ZIP files apply? I mean, if the file extension is ignored because file is used to determine the type, mc should just treat is as ZIP file.
The zip-by-type rules in mc.ext.ini should apply here, but why is it ignored?

[zip-by-type]
Type=\\(Zip archive
Open=%cd %p/uzip://
View=%view{ascii} /usr/lib/mc/ext.d/archive.sh view zip

[ibm5110]

Perhaps there is a bug within file. This is what I get with the parameters suggested in #4862 :

# file -z -b -L -S Public_Release.jar
ERROR:[gzip: ] (data)
# file -b -L -S Public_Release.jar
Zip archive data, made by v2.0 UNIX, extract using at least v2.0, last modified Dec 05 2025 14:10:42, uncompressed size 0, method=deflate

[zyv]

Perhaps there is a bug within file. This is what I get with the parameters suggested in #4862:

# file -z -b -L -S Public_Release.jar
ERROR:[gzip: ] (data)

This would explain it. Either there is something wrong with the specific file, or you hit a bug in the file utility.