Fix M1 Mac build

ClientLibrary/Dockerfile

@@ -2,7 +2,7 @@
 #
 # See README.md for usage instructions.
 
-FROM ubuntu:18.04
+FROM --platform=linux/amd64 ubuntu:18.04
 
 # Install system-level dependencies.
 ENV DEBIAN_FRONTEND=noninteractive

ClientLibrary/README.md

@@ -60,6 +60,7 @@ Note that you may need to use `sudo docker` below, depending on your OS.
 ```bash
 cd .. && \
   docker run \
+  --platform=linux/amd64 \
   --rm \
   -v $PWD:/go/src/github.com/Psiphon-Labs/psiphon-tunnel-core \
   psiclientlibrary-builder \

ConsoleClient/Dockerfile

@@ -2,7 +2,7 @@
 #
 # See README.md for usage instructions.
 
-FROM ubuntu:18.04
+FROM --platform=linux/amd64 ubuntu:18.04
 
 # Install system-level dependencies.
 ENV DEBIAN_FRONTEND=noninteractive

ConsoleClient/README.md

@@ -17,6 +17,7 @@ Note that you may need to use `sudo docker` below, depending on your OS.
 ```bash
 cd .. && \
   docker run \
+  --platform=linux/amd64 \
   --rm \
   -v $PWD:/go/src/github.com/Psiphon-Labs/psiphon-tunnel-core \
   psiclient \

MobileLibrary/Android/Dockerfile

@@ -2,10 +2,13 @@
 #
 # See README.md for usage instructions.
 
-FROM ubuntu:18.04
+FROM --platform=linux/amd64 ubuntu:18.04
 
 # Install system-level dependencies.
 ENV DEBIAN_FRONTEND=noninteractive
+
+RUN mkdir -p /usr/share/man/man1 # fixes https://stackoverflow.com/a/69844974
+
 RUN apt-get update -y && apt-get install -y --no-install-recommends \
     build-essential \
     ca-certificates \

MobileLibrary/Android/README.md

@@ -51,6 +51,7 @@ Note that you may need to use `sudo docker` below, depending on your OS.
 ```bash
 cd ../.. && \
   docker run \
+  --platform=linux/amd64 \
   --rm \
   -v $(pwd):/go/src/github.com/Psiphon-Labs/psiphon-tunnel-core \
   psiandroid \