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Been wondering how to make use of the electrumx server, but in bash. First I needed to connect to the electrumx server. #!/bin/bash echo "get block header" (echo '{"method" : "blockchain.block.header", "params": ["1"], "id": "msg_id"}'; sleep 1) | ncat --ssl electrumx1.denarius.pro 50002 This outputs. block header {"jsonrpc": "2.0", "result": "06000000cd8f82c4c28201fd89def0dba541d66432bff9c1bb16fc1c6201dabb5d0d0000e4abd1522f390c5a2b83add7c8d29b875e1e0691dc43267f0406e9ddfea329c76ab74159ffff0f1e000d8425", "id": "msg_id"} So now to get a balance. The thing with electrumx server is that you need a scripthash to call any address functions. But I don't have that. All I have is a bash terminal and a Denarius address. So what do I do? Line by line dissect how people create an address and then work backwards to the scripthash. I need this image, but down to up. source: https://learnmeabitcoin.com/guide/p2pkh This is not so easy as I can't find anyone doing this backwards in bash. But I found lots of posts how to go forwards. Here is how to get it before converting to big endian. #!/bin/bash . denarius.sh #DUP HASH160 begin="76A914" echo $begin #EQUALVERIFY CHECKSIG end="88AC" echo $end echo "decodeBase58" decoded="$(decodeBase58 DCMRvR6MUppPgP8vrMKuni4FL5de8SjicG)" echo "Remove 00 bytes" echo ${decoded#??} removefront=$(echo "${decoded#??}") echo $removefront echo "Remove checksum" removeback=$(echo "${removefront%????????}") echo "95 characters base58" echo $removeback echo "now what?" echo $begin$removeback$end echo "convert to scripthash" echo -n $begin$removeback$end | xxd -r -p | sha256sum | cut -d' ' -f1 scripthash=$(echo -n $begin$removeback$end | xxd -r -p | sha256sum | cut -d' ' -f1) echo $scripthash Will also need grondilu bitcoin-bash-tools. https://github.com/grondilu/bitcoin-bash-tools Get the bitcoin.sh and throw that into the same directory you are going to test this out in, for obvious reasons I renamed bitcoin.sh to denarius.sh. First I am assuming a standard P2PKH address with OP_DUP OP_HASH160 hashedpublickey OP_EQUALVERIFY OP_CHECKSIG #DUP HASH160 begin="76A914" echo $begin #EQUALVERIFY CHECKSIG end="88AC" echo $end Then decodeBase58 of our Denarius address, works on bitcoin obviously. echo "decodeBase58" decoded="$(decodeBase58 DCMRvR6MUppPgP8vrMKuni4FL5de8SjicG)" Then remove 00 bytes from the front of this. The #?? removes 2 characters from the left of a string. echo "Remove 00 bytes" echo ${decoded#??} removefront=$(echo "${decoded#??}") echo $removefront Now remove the checksum. The %???????? removes 8 characters from the right of the string. echo "Remove checksum" removeback=$(echo "${removefront%????????}") echo "95 characters base58" echo $removeback Now what? How to convert to scripthash? We can echo the the uncompressed public key, kind of. echo "now what?" echo $begin$removeback$end echo "convert to scripthash" sha256 this in proper format, using xxd and then sha256 that. echo -n $begin$removeback$end | xxd -r -p | sha256sum | cut -d' ' -f1 scripthash=$(echo -n $begin$removeback$end | xxd -r -p | sha256sum | cut -d' ' -f1) echo $scripthash At the end from that address I get. 3735fe8239322122222f8a8f42d9b6545bc517e2086116e57953fdc9cc7f6115 For now I have a separate function I found to convert to big endian, since electrumx server wants it this way. source: https://electrumx.readthedocs.io/en/latest/protocol-basics.html#script-hashes #!/bin/bash #echo 6191c3b590bfcfa0475e877c302da1e323497acf3b42c08d8fa28e364edf018b | ./bigendian.sh #8b01df4e368ea28f8dc0423bcf7a4923e3a12d307c875e47a0cfbf90b5c39161 # check stdin if [ -t 0 ]; then exit; fi v=`cat /dev/stdin` i=${#v} while [ $i -gt 0 ] do i=$[$i-2] echo -n ${v:$i:2} done echo I run this like echo 3735fe8239322122222f8a8f42d9b6545bc517e2086116e57953fdc9cc7f6115 | ./bigendian.sh and get the scripthash electrumx server wants 15617fccc9fd5379e5166108e217c55b54b6d9428f8a2f222221323982fe3537 Like bash magic we can use that scripthash to talk to the electrumx server to get a balance. #!/bin/bash echo "get balance" (echo '{"method" : "blockchain.scripthash.get_balance", "params": ["15617fccc9fd5379e5166108e217c55b54b6d9428f8a2f222221323982fe3537"], "id": "msg_id"}'; sleep 1) | ncat --ssl electrumx1.denarius.pro 50002 And we get the balance. get balance {"jsonrpc": "2.0", "result": {"confirmed": 125740854, "unconfirmed": 0}, "id": "msg_id"} And a large step forward in creating a basic terminal wallet for any device that can use bash, ncat and has port 50002 open.