Async operations about visa-rs

[dr-kernel]

Something that's not entirely clear from your readme is whether the NI_VISA library is required, or will libvisa work as well?

I ask this because when trying to use async_write using libvisa and i get:

  = note: /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.02.rcgu.o): In function `visa_rs::async_
io::AsyncIoHandler::new':
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN7visa_rs8async_io14AsyncIoHandler3new17h212d79d7ae1c5689E+0x221): undefined reference to `viInstallHandler'
          /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.02.rcgu.o): In function `<visa_rs::async
_io::AsyncIoHandler as core::ops::drop::Drop>::drop':
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN75_$LT$visa_rs..async_io..AsyncIoHandler$u20$as$u20$core..ops..drop..Drop$GT$4drop17h84ef7ecf876e51e3E+0xe4): undefined reference to `viTerminate'
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN75_$LT$visa_rs..async_io..AsyncIoHandler$u20$as$u20$core..ops..drop..Drop$GT$4drop17h84ef7ecf876e51e3E+0x1dc): undefined reference to `viUninstallHandler'
          /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.05.rcgu.o): In function `visa_rs::instru
ment::Instrument::visa_write_async':
          visa_rs.bcfb2d0a6785fd0b-cgu.05:(.text._ZN7visa_rs10instrument10Instrument16visa_write_async17h4a91cc3f7856106eE+0x24): undefined reference to `viWriteAsync'
          collect2: error: ld returned 1 exit status

Appreciate you're feedback on this.
~Dustin

[TsuITOAR]

Something that's not entirely clear from your readme is whether the NI_VISA library is required, or will libvisa work as well?

I ask this because when trying to use async_write using libvisa and i get:

  = note: /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.02.rcgu.o): In function `visa_rs::async_
io::AsyncIoHandler::new':
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN7visa_rs8async_io14AsyncIoHandler3new17h212d79d7ae1c5689E+0x221): undefined reference to `viInstallHandler'
          /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.02.rcgu.o): In function `<visa_rs::async
_io::AsyncIoHandler as core::ops::drop::Drop>::drop':
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN75_$LT$visa_rs..async_io..AsyncIoHandler$u20$as$u20$core..ops..drop..Drop$GT$4drop17h84ef7ecf876e51e3E+0xe4): undefined reference to `viTerminate'
          visa_rs.bcfb2d0a6785fd0b-cgu.02:(.text._ZN75_$LT$visa_rs..async_io..AsyncIoHandler$u20$as$u20$core..ops..drop..Drop$GT$4drop17h84ef7ecf876e51e3E+0x1dc): undefined reference to `viUninstallHandler'
          /build/private/cargo-target/release/deps/libvisa_rs-de0f39bbca939597.rlib(visa_rs-de0f39bbca939597.visa_rs.bcfb2d0a6785fd0b-cgu.05.rcgu.o): In function `visa_rs::instru
ment::Instrument::visa_write_async':
          visa_rs.bcfb2d0a6785fd0b-cgu.05:(.text._ZN7visa_rs10instrument10Instrument16visa_write_async17h4a91cc3f7856106eE+0x24): undefined reference to `viWriteAsync'
          collect2: error: ld returned 1 exit status

Appreciate you're feedback on this. ~Dustin

Hi, in principle any visa library should work if it follows the specifications.
It seems that libvisa uses the specification distributed in 06-18-2012, while I generate the prebindings in visa-sys based on distribution in 10-30-2020, maybe that's the problem. You can try rebinding by setting env var INCLUDE_PATH_VAR and open its bindgen feature (check the build.rs of visa-sys).

EDIT: NI-visa use the visa version 5.8 while libvisa using 5.1, there should be no version problem since NI VISA works fine.

BTW, do all methods fail or just this one?

[dr-kernel]

I have only tried async_write and write_all (from the example). write_all compiles and links correctly.
I should also note that I have to create a symlink of libvisa -> libvisa64 for linking to work since that name is hard coded, it would be nice if this was a env_var or flag as part of the build.
I have found rsvisa, i could also try and see if that provides the bindings.

Interestingly those functions do exist in the visa.h file that the source (libvisa-dev) provides. I'm curious why those methods don't end up in the compiled .so.