1 Long: proto 2 Arg: <protocols> 3 Help: Enable/disable PROTOCOLS 4 See-also: proto-redir proto-default 5 Added: 7.20.2 6 Category: connection curl 7 --- 8 Tells curl to limit what protocols it may use for transfers. Protocols are 9 evaluated left to right, are comma separated, and are each a protocol name or 10 \&'all', optionally prefixed by zero or more modifiers. Available modifiers are: 11 .RS 12 .TP 3 13 .B + 14 Permit this protocol in addition to protocols already permitted (this is 15 the default if no modifier is used). 16 .TP 17 .B - 18 Deny this protocol, removing it from the list of protocols already permitted. 19 .TP 20 .B = 21 Permit only this protocol (ignoring the list already permitted), though 22 subject to later modification by subsequent entries in the comma separated 23 list. 24 .RE 25 .IP 26 For example: 27 .RS 28 .TP 15 29 .B --proto -ftps 30 uses the default protocols, but disables ftps 31 .TP 32 .B --proto -all,https,+http 33 only enables http and https 34 .TP 35 .B --proto =http,https 36 also only enables http and https 37 .RE 38 .IP 39 Unknown protocols produce a warning. This allows scripts to safely rely on 40 being able to disable potentially dangerous protocols, without relying upon 41 support for that protocol being built into curl to avoid an error. 42 43 This option can be used multiple times, in which case the effect is the same 44 as concatenating the protocols into one instance of the option. 45