$ openssl genrsa -aes128 -out fd.key 2048
Generating RSA private key, 2048 bit long modulus
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e is 65537 (0x10001)
Enter pass phrase for fd.key:
73496:error:28069065:lib(40):UI_set_result:result too small:/BuildRoot/Library/Caches/com.apple.xbs/Sources/OpenSSL098/OpenSSL098-64/src/crypto/ui/ui_lib.c:850:You must type in 4 to 1023 characters
Enter pass phrase for fd.key:
73496:error:28069065:lib(40):UI_set_result:result too small:/BuildRoot/Library/Caches/com.apple.xbs/Sources/OpenSSL098/OpenSSL098-64/src/crypto/ui/ui_lib.c:850:You must type in 4 to 1023 characters
Enter pass phrase for fd.key:
Enter pass phrase for fd.key:
Enter pass phrase for fd.key:
Enter pass phrase for fd.key:
Enter pass phrase for fd.key:
Enter pass phrase for fd.key:
Verifying - Enter pass phrase for fd.key: