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gripped

Member

From: UK

Registered: 2013-03-15

Posts: 13

Website

PGKBUILD 'provides' 'depends' switch to library name

I've noticed various PKGBUILD's move to using library .so names in provides and depends rather than package names.

e.g.

in the latest ffmpeg 2.7.2-1

depends=(
      'alsa-lib' 'bzip2' 'fontconfig' 'fribidi' 'gnutls' 'gsm' 'lame' 'libass'
      'libbluray' 'libmodplug' 'libpulse' 'libssh' 'libtheora' 'libva'
      'libvdpau' 'libwebp' 'opencore-amr' 'openjpeg' 'opus' 'schroedinger'
      'sdl' 'speex' 'v4l-utils' 'xvidcore' 'zlib'
      'libvorbis.so' 'libvorbisenc.so' 'libvpx.so' 'libx264.so' 'libx265.so'

provides=(
      'libavcodec.so' 'libavdevice.so' 'libavfilter.so' 'libavformat.so'
      'libavresample.so' 'libavutil.so' 'libpostproc.so' 'libswresample.so'
      'libswscale.so'
)

I'm curious as to the reasoning and benefits behind this but searching has not shed any light on it for me.

Does any one know why or have a link to a discussion ?

jasonwryan

Anarchist

From: .nz

Registered: 2009-05-09

Posts: 30,424

Website

Re: PGKBUILD 'provides' 'depends' switch to library name

depends...
If the dependency name appears to be a library (ends with .so), makepkg will try to find a binary that depends on the library in the built
package and append the version needed by the binary. Appending the version yourself disables automatic detection.

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gripped

Member

From: UK

Registered: 2013-03-15

Posts: 13

Website

Re: PGKBUILD 'provides' 'depends' switch to library name

depends...
If the dependency name appears to be a library (ends with .so), makepkg will try to find a binary that depends on the library in the built
package and append the version needed by the binary. Appending the version yourself disables automatic detection.

Thanks but that I can find

As I said "I'm curious as to the reasoning and benefits behind this".

arojas

Developer

From: Spain

Registered: 2011-10-09

Posts: 2,098

Re: PGKBUILD 'provides' 'depends' switch to library name

For one thing, it will prevent users who (wrongly) do partial updates from breaking their system after a library soname bump.