RPC_SOC(3)

📦

version 15.1 · 2 versions

15.1 · freebsd 15.1 (latest)
14.5 · freebsd 14.5

💅 RPC_SOC(3) — library routines for remote procedure calls ✨

okay so this is the legacy TS-RPC corner of the library, and the manual page is literally called RPC_SOC(3). It is a lot. Buckle up, bestie. 🎀

✨ NAME ✨

This page documents: rpc_soc, auth_destroy, authnone_create, authunix_create, authunix_create_default, callrpc, clnt_broadcast, clnt_call, clnt_control, clnt_create, clnt_destroy, clnt_freeres, clnt_geterr, clnt_pcreateerror, clnt_perrno, clnt_perror, clnt_spcreateerror, clnt_sperrno, clnt_sperror, clntraw_create, clnttcp_create, clntudp_bufcreate, clntudp_create, clntunix_create, get_myaddress, pmap_getmaps, pmap_getport, pmap_rmtcall, pmap_set, pmap_unset, registerrpc, rpc_createerr, svc_destroy, svc_fds, svc_fdset, svc_getargs, svc_getcaller, svc_getreq, svc_getreqset, svc_register, svc_run, svc_sendreply, svc_unregister, svcerr_auth, svcerr_decode, svcerr_noproc, svcerr_noprog, svcerr_progvers, svcerr_systemerr, svcerr_weakauth, svcfd_create, svcunixfd_create, svcraw_create, svcunix_create, xdr_accepted_reply, xdr_authunix_parms, xdr_callhdr, xdr_callmsg, xdr_opaque_auth, xdr_pmap, xdr_pmaplist, xdr_rejected_reply, xdr_replymsg, xprt_register, xprt_unregister.

🫶 LIBRARY 🫶

Standard C Library (libc, -lc) — yes bestie, that’s the one. 💖

🌸 SYNOPSIS 🌸

#include <rpc/rpc.h>

See “DESCRIPTION” for function declarations.

🦋 DESCRIPTION 🦋

The svc_*() and clnt_*() functions described in this page are the old, TS-RPC interface to the XDR and RPC library, and exist for backward compatibility. The new interface is described in the pages referenced from rpc(3). 👑

These routines allow C programs to make procedure calls on other machines across the network. First, the client calls a procedure to send a data packet to the server. Upon receipt of the packet, the server calls a dispatch routine to perform the requested service, and then sends back a reply. Finally, the procedure call returns to the client. No cap, that’s the whole little dance. 💃

Routines that are used for Secure RPC (DES authentication) are described in rpc_secure(3). Secure RPC can be used only if DES encryption is available. 🔐

🎀 `auth_destroy`

void
auth_destroy(AUTH *auth)

A macro that destroys the authentication information associated with auth. Destruction usually involves deallocation of private data structures. The use of auth is undefined after calling auth_destroy(). So yeah, after this call, auth is giving “no thoughts, head empty” — do not touch it. 💀

🌈 `authnone_create`

AUTH *
authnone_create()

Create and return an RPC authentication handle that passes nonusable authentication information with each remote procedure call. This is the default authentication used by RPC. It’s iconic in a “I bring nothing to the function” kind of way. ✨

🍓 `authunix_create`

AUTH *
authunix_create(char *host, u_int uid, u_int gid, int len, u_int *aup_gids)

Create and return an RPC authentication handle that contains Unix authentication information. The host argument is the name of the machine on which the information was created; uid is the user’s user ID; gid is the user’s current group ID; len and aup_gids refer to a counted array of groups to which the user belongs. It is easy to impersonate a user. 🫣 Yeah, she said it, not me — security girlies, take notes.

🧚 `authunix_create_default`

AUTH *
authunix_create_default()

Calls authunix_create() with the appropriate arguments. Default queen behavior, honestly. 👑

🔥 `callrpc`

int callrpc(char *host, u_long prognum, u_long versnum, u_long procnum,
        xdrproc_t inproc, void *in, xdrproc_t outproc, void *out)

Call the remote procedure associated with prognum, versnum, and procnum on the machine host. The in argument is the address of the procedure’s argument(s), and out is the address of where to place the result(s); inproc is used to encode the procedure’s arguments, and outproc is used to decode the procedure’s results. This routine returns zero if it succeeds, or the value of enum clnt_stat cast to an integer if it fails. The routine clnt_perrno() is handy for translating failure statuses into messages. 🫶

⚠️ Warning: calling remote procedures with this routine uses UDP/IP as a transport; see clntudp_create() for restrictions. You do not have control of timeouts or authentication using this routine. So lowkey no timeout remote, bestie. 😭

🌟 `clnt_broadcast`

enum clnt_stat
clnt_broadcast(u_long prognum, u_long versnum, u_long procnum,
        xdrproc_t inproc, char *in, xdrproc_t outproc, char *out,
        bool_t (*eachresult)(caddr_t, struct sockaddr_in *))

Like callrpc(), except the call message is broadcast to all locally connected broadcast nets. Each time it receives a response, this routine calls eachresult(), whose form is:

bool_t eachresult(caddr_t out, struct sockaddr_in *addr)

where out is the same as out passed to clnt_broadcast(), except that the remote procedure’s output is decoded there; addr points to the address of the machine that sent the results. If eachresult() returns zero, clnt_broadcast() waits for more replies; otherwise it returns with appropriate status. It’s giving “reply guys welcome” energy. 💅

⚠️ Warning: broadcast sockets are limited in size to the maximum transfer unit of the data link. For ethernet, this value is 1500 bytes. ✨

💜 `clnt_call`

enum clnt_stat
clnt_call(CLIENT *clnt, u_long procnum, xdrproc_t inproc, char *in,
        xdrproc_t outproc, char *out, struct timeval tout)

A macro that calls the remote procedure procnum associated with the client handle, clnt, which is obtained with an RPC client creation routine such as clnt_create(). The in argument is the address of the procedure’s argument(s), and out is the address of where to place the result(s); inproc is used to encode the procedure’s arguments, and outproc is used to decode the procedure’s results; tout is the time allowed for results to come back. Tick tock, bestie. ⏰

🦋 `clnt_destroy`

void clnt_destroy(CLIENT *clnt)

A macro that destroys the client’s RPC handle. Destruction usually involves deallocation of private data structures, including clnt itself. Use of clnt is undefined after calling clnt_destroy(). If the RPC library opened the associated socket, it will close it also. Otherwise, the socket remains open. So like, sometimes it cleans up, sometimes the socket is still outside living its best life. 🙈

👑 `clnt_create`

CLIENT *
clnt_create(char *host, u_long prog, u_long vers, char *proto)

Generic client creation routine. The host argument identifies the name of the remote host where the server is located. The proto argument indicates which kind of transport protocol to use. The currently supported values for this field are "udp" and "tcp". Default timeouts are set, but can be modified using clnt_control(). ✨

⚠️ Warning: Using UDP has its shortcomings. Since UDP-based RPC messages can only hold up to 8 Kbytes of encoded data, this transport cannot be used for procedures that take large arguments or return huge results. No giant results over UDP, bestie. 😭

💅 `clnt_control`

bool_t
clnt_control(CLIENT *cl, u_int req, char *info)

A macro used to change or retrieve various information about a client object. The req argument indicates the type of operation, and info is a pointer to the information. For both UDP and TCP, the supported values of req and their argument types and what they do are:

CLSET_TIMEOUT — struct timeval — set total timeout
CLGET_TIMEOUT — struct timeval — get total timeout

📝 Note: if you set the timeout using clnt_control(), the timeout argument passed to clnt_call() will be ignored in all future calls. She said what she said. 🫶

CLGET_SERVER_ADDR — struct sockaddr_in — get server’s address

The following operations are valid for UDP only:

CLSET_RETRY_TIMEOUT — struct timeval — set the retry timeout
CLGET_RETRY_TIMEOUT — struct timeval — get the retry timeout

The retry timeout is the time that UDP RPC waits for the server to reply before retransmitting the request. So it’s the “bestie, are you still there?” timer. ⏳

🎀 `clnt_freeres`

bool_t clnt_freeres(CLIENT *clnt, xdrproc_t outproc, char *out)

A macro that frees any data allocated by the RPC/XDR system when it decoded the results of an RPC call. The out argument is the address of the results, and outproc is the XDR routine describing the results. This routine returns one if the results were successfully freed, and zero otherwise. Cleanup era. 🧹

🌸 `clnt_geterr`

void
clnt_geterr(CLIENT *clnt, struct rpc_err *errp)

A macro that copies the error structure out of the client handle to the structure at address errp. Error info, but make it transferable. 💌

🫶 `clnt_pcreateerror`

void
clnt_pcreateerror(char *s)

prints a message to standard error indicating why a client RPC handle could not be created. The message is prepended with string s and a colon. A newline is appended at the end of the message. Used when a clnt_create(), clntraw_create(), clnttcp_create(), or clntudp_create() call fails. When creation flops, this is the one who tells you why. 😭

⭐ `clnt_perrno`

void
clnt_perrno(enum clnt_stat stat)

Print a message to standard error corresponding to the condition indicated by stat. A newline is appended at the end of the message. Used after callrpc(). Short and to the point. 💅

🍓 `clnt_perror`

void clnt_perror(CLIENT *clnt, char *s)

Print a message to standard error indicating why an RPC call failed; clnt is the handle used to do the call. The message is prepended with string s and a colon. A newline is appended at the end of the message. Used after clnt_call(). So like, when the call says “it’s not me, it’s the RPC,” this translates the drama. 🎀

🧚 `clnt_spcreateerror`

char *
clnt_spcreateerror(char *s)

Like clnt_pcreateerror(), except that it returns a string instead of printing to the standard error.

🐛 Bugs: returns pointer to static data that is overwritten on each call. Bestie, it’s a reusable scratchpad, not a keepsake. Do not hold onto it. 💀

🌈 `clnt_sperrno`

char *
clnt_sperrno(enum clnt_stat stat)

Take the same arguments as clnt_perrno(), but instead of sending a message to the standard error indicating why an RPC call failed, return a pointer to a string which contains the message. ✨

The clnt_sperrno() function is used instead of clnt_perrno() if the program does not have a standard error (as a program running as a server quite likely does not), or if the programmer does not want the message to be output with printf(), or if a message format different from that supported by clnt_perrno() is to be used. It’s giving “I bring the message to you” energy. 🫶

📝 Note: unlike clnt_sperror() and clnt_spcreateerror(), clnt_sperrno() returns pointer to static data, but the result will not get overwritten on each call. So this one is the stable static-data icon. 👑

💜 `clnt_sperror`

char *
clnt_sperror(CLIENT *rpch, char *s)

Like clnt_perror(), except that (like clnt_sperrno()) it returns a string instead of printing to standard error. String-returning error messenger, slay. 💌

Bugs: returns pointer to static data that is overwritten on each call. 💀 Yeah bestie, that's the fine print on the one above — every call stomps the same buffer, so copy what you need before you call it again. No cap.

🧸 `CLIENT *clntraw_create(u_long prognum, u_long versnum)`

CLIENT *
clntraw_create(u_long prognum, u_long versnum)

Okay so this one makes a lil toy RPC client for the remote program prognum, version versnum. And when I say toy, I mean the "transport" that's supposedly passing your messages to the service is literally just a buffer inside your own process's address space 😭 so the matching RPC server has to live in the same address space — peep svcraw_create(). It's giving dress rehearsal energy: you get to simulate RPC and measure RPC overheads (round trip times, all that) with zero kernel interference. Iconic for benchmarking. Returns NULL if it fails.

🌐 `CLIENT *clnttcp_create(...)`

CLIENT *
clnttcp_create(struct sockaddr_in *addr, u_long prognum, u_long versnum,
        int *sockp, u_int sendsz, u_int recvsz)

Creates an RPC client for remote program prognum, version versnum, riding on TCP/IP as the transport. The remote program chills at Internet address addr. If addr->sin_port is zero, it gets set to the actual port the remote program is listening on (it goes and asks the remote rpcbind(8) service for the deets). The sockp argument is a socket; if it's RPC_ANYSOCK, this routine opens a fresh one and sets sockp for you 🫶. Since TCP-based RPC uses buffered I/O, you the user get to pick the send and receive buffer sizes with sendsz and recvsz; values of zero mean "choose suitable defaults, queen." Returns NULL if it fails.

📨 `CLIENT *clntudp_create(...)`

CLIENT *
clntudp_create(struct sockaddr_in *addr, u_long prognum, u_long versnum,
        struct timeval wait, int *sockp)

Creates an RPC client for remote program prognum, version versnum, this time on UDP/IP. Remote program lives at Internet address addr. If addr->sin_port is zero, it's set to the actual port the remote program is listening on (again, the remote rpcbind(8) service gets consulted). sockp is a socket; if it's RPC_ANYSOCK, this routine opens a new one and sets sockp. The UDP transport resends the call message in intervals of wait time until a response shows up or the call times out. The total time for the call to time out is specified by clnt_call().

⚠️ Warning: since UDP-based RPC messages can only hold up to 8 Kbytes of encoded data, this transport cannot be used for procedures that take large arguments or return huge results. So if your payload is thicc, pick a different transport. Periodt.

📦 `CLIENT *clntudp_bufcreate(...)`

CLIENT *
clntudp_bufcreate(struct sockaddr_in *addr, u_long prognum,
        u_long versnum, struct timeval wait, int *sockp,
        unsigned int sendsize, unsigned int recosize)

Same vibe as the last one — creates an RPC client for remote program prognum, on versnum, using UDP/IP as the transport. The remote program is located at Internet address addr. If addr->sin_port is zero, it's set to the actual port that the remote program is listening on (yep, the remote rpcbind(8) service is consulted for this info). The sockp argument is a socket; if it's RPC_ANYSOCK, this routine opens a new one and sets sockp. The UDP transport resends the call message in intervals of wait time until a response arrives or the call times out. The total time to time out is specified by clnt_call().

The ✨ upgrade ✨ here: this lets you specify the maximum packet size for sending and receiving UDP-based RPC messages. (recosize is spelled exactly like that, don't @ me — that's the header's business 💅)

🦋 `CLIENT *clntunix_create(...)`

CLIENT *
clntunix_create(struct sockaddr_un *raddr, u_long prognum,
        u_long versnum, int *sockp, u_int sendsz, u_int recvsz)

Creates an RPC client for the local program prognum, version versnum, using Unix-domain sockets as the transport. The local program is located at the *raddr. The sockp argument is a socket; if it's RPC_ANYSOCK, this routine opens a new one and sets sockp. Since Unix-based RPC uses buffered I/O, you may specify the send and receive buffer sizes with sendsz and recvsz; values of zero pick suitable defaults for you 💖. Returns NULL if it fails.

🏠 `int get_myaddress(struct sockaddr_in *addr)`

int
get_myaddress(struct sockaddr_in *addr)

Stuffs the machine's IP address straight into addr, without consulting the library routines that deal with /etc/hosts. Independent queen behavior honestly. The port number is always set to htons(PMAPPORT). Returns zero on success, non-zero on failure.

🗺️ `struct pmaplist pmap_getmaps(struct sockaddr_in addr)`

struct pmaplist *
pmap_getmaps(struct sockaddr_in *addr)

A user interface to the rpcbind(8) service that hands you back a list of the current RPC program-to-port mappings on the host located at IP address addr. Heads up: this routine can return NULL 😭. Fun fact: the command rpcinfo -p uses this routine. So when you type that, this is the girl doing the work.

🔍 `u_short pmap_getport(...)`

u_short
pmap_getport(struct sockaddr_in *addr, u_long prognum, u_long versnum,
        u_long protocol)

Another user interface to the rpcbind(8) service — this one returns the port number where a service is waiting that supports program number prognum, version versnum, and speaks the transport protocol associated with protocol. The value of protocol is most likely IPPROTO_UDP or IPPROTO_TCP. A return value of zero means either the mapping doesn't exist, or the RPC system failed to contact the remote rpcbind(8) service. In that latter case, the global variable rpc_createerr holds the RPC status. So like… zero is doing double duty, check rpc_createerr before you spiral 🙈.

📡 `enum clnt_stat pmap_rmtcall(...)`

enum clnt_stat
pmap_rmtcall(struct sockaddr_in *addr, u_long prognum, u_long versnum,
        u_long procnum, xdrproc_t inproc, char *in, xdrproc_t outproc,
        char *out, struct timeval tout, u_long *portp)

A user interface to the rpcbind(8) service that instructs rpcbind(8) on the host at IP address addr to make an RPC call on your behalf to a procedure on that host. The portp argument gets modified to the program's port number if the procedure succeeds. The definitions of the other arguments are discussed in callrpc() and clnt_call(). This procedure should be used for a "ping" and nothing else, fr fr — don't go building your whole app on it. See also clnt_broadcast().

📌 `bool_t pmap_set(...)`

bool_t pmap_set(u_long prognum, u_long versnum, u_long protocol, u_short
        port)

A user interface to the rpcbind(8) service that establishes a mapping between the triple (prognum, versnum, protocol) and port on the machine's rpcbind(8) service. The value of protocol is most likely IPPROTO_UDP or IPPROTO_TCP. Returns one if it succeeds, zero otherwise. And plot twist: this is automatically done by svc_register() 🎀 so you usually don't have to lift a finger.

🧹 `bool_t pmap_unset(u_long prognum, u_long versnum)`

bool_t pmap_unset(u_long prognum, u_long versnum)

A user interface to the rpcbind(8) service that destroys all mapping between the triple (prognum, versnum, *) and ports on the machine's rpcbind(8) service. Note the * bestie — it wipes every protocol for that program/version combo. Returns one if it succeeds, zero otherwise. Cleanup queen energy 🧼

📝 `bool_t registerrpc(...)`

bool_t registerrpc(u_long prognum, u_long versnum, u_long procnum,
        char *(*procname)(void), xdrproc_t inproc, xdrproc_t outproc)

Register procedure procname with the RPC service package. When a request arrives for program prognum, version versnum, and procedure procnum, procname is called with a pointer to its argument(s); progname should return a pointer to its static result(s); inproc is used to decode the arguments while outproc is used to encode the results. Returns zero if the registration succeeded, -1 otherwise.

⚠️ Warning: remote procedures registered in this form are accessed using the UDP/IP transport; see svcudp_create() for restrictions. So yeah, the 8 Kbyte thing applies — plan accordingly.

🚨 `struct rpc_createerr rpc_createerr;`

struct rpc_createerr rpc_createerr;

A global variable whose value gets set by any RPC client creation routine that does not succeed 😭. Use the routine clnt_pcreateerror() to print out the reason why. Translation: when something goes wrong, this is where the receipts live — go read them.

💥 `bool_t svc_destroy(SVCXPRT *xprt)`

bool_t svc_destroy(SVCXPRT * xprt)

A macro that destroys the RPC service transport handle, xprt. Destruction usually involves deallocation of private data structures, including xprt itself. Use of xprt is undefined after calling this routine — so like, do not touch it afterwards, bestie, that's a use-after-free waiting to happen 💀

🎛️ `fd_set svc_fdset;`

fd_set svc_fdset;

A global variable reflecting the RPC service side's read file descriptor bit mask; it's suitable as a template argument to the select(2) system call. This is only of interest if a service implementor does not call svc_run(), but instead does their own asynchronous event processing (main character energy, honestly). This variable is read-only — do not pass its address to select(2)! 🙅‍♀️ — yet it may change after calls to svc_getreqset() or any creation routines. Also note: if the process has descriptor limits which are extended beyond FD_SETSIZE, this variable will only be usable for the first FD_SETSIZE descriptors.

🕰️ `int svc_fds;`

int svc_fds;

Similar to svc_fdset, but limited to 32 descriptors. This interface is obsoleted by svc_fdset — so it's giving legacy, sweetie, we don't really use it anymore.

🗑️ `bool_t svc_freeargs(SVCXPRT xprt, xdrproc_t inproc, char in)`

bool_t svc_freeargs(SVCXPRT *xprt, xdrproc_t inproc, char *in)

A macro that frees any data allocated by the RPC/XDR system when it decoded the arguments to a service procedure using svc_getargs(). Returns 1 if the results were successfully freed, and zero otherwise. Free your memory, queen, it's self care 🌸

🎁 `bool_t svc_getargs(SVCXPRT xprt, xdrproc_t inproc, char in)`

bool_t svc_getargs(SVCXPRT *xprt, xdrproc_t inproc, char *in)

A macro that decodes the arguments of an RPC request associated with the RPC service transport handle, xprt. The in argument is the address where the arguments will be placed; inproc is the XDR routine used to decode them. Returns one if decoding succeeds, and zero otherwise.

📞 `struct sockaddr_in svc_getcaller(SVCXPRT xprt)`

struct sockaddr_in *
svc_getcaller(SVCXPRT *xprt)

The approved way of getting the network address of the caller of a procedure associated with the RPC service transport handle, xprt. Approved!! Like, this is the sanctioned method, don't go poking at structs yourself 💅

🔔 `void svc_getreqset(fd_set *rdfds)`

void svc_getreqset(fd_set *rdfds)

This routine is only of interest if a service implementor does not call svc_run(), but instead implements custom asynchronous event processing. It gets called when the select(2) system call has determined that an RPC request has arrived on some RPC socket(s); rdfds is the resultant read file descriptor bit mask. The routine returns when all sockets associated with the value of rdfds have been serviced. So it handles the whole batch and then dips ✨

🔁 `void svc_getreq(int rdfds)`

void svc_getreq(int rdfds)

Similar to svc_getreqset(), but limited to 32 descriptors. This interface is obsoleted by svc_getreqset(). 💀 (bestie it's giving legacy — use the new one)

bool_t svc_register(SVCXPRT *xprt, u_long prognum, u_long versnum, void (*dispatch)(struct svc_req *, SVCXPRT *), int protocol)

Okay so this one associates prognum and versnum with the service dispatch procedure, dispatch(). ✨ If protocol is zero, the service is not registered with the rpcbind(8) service. If protocol is non-zero, then a mapping of the triple (prognum, versnum, protocol) to xprt->xp_port is established with the local rpcbind(8) service — and generally protocol is zero, IPPROTO_UDP or IPPROTO_TCP, iykyk. 🫶

The procedure dispatch() has the following form:

bool_t dispatch(struct svc_req *request, SVCXPRT *xprt)

The svc_register() routine returns one if it succeeds, and zero otherwise. 🎀

svc_run()

This routine never returns. 😭 Not me waiting forever — literally. It waits for RPC requests to arrive, and calls the appropriate service procedure using svc_getreq() when one arrives. This procedure is usually waiting for a select(2) system call to return. 💅

bool_t svc_sendreply(SVCXPRT *xprt, xdrproc_t outproc, char *out)

Called by an RPC service's dispatch routine to send the results of a remote procedure call. The xprt argument is the request's associated transport handle; outproc is the XDR routine which is used to encode the results; and out is the address of the results. This routine returns one if it succeeds, zero otherwise. 🌸

void svc_unregister(u_long prognum, u_long versnum)

Remove all mapping of the double (prognum, versnum) to dispatch routines, and of the triple (prognum, versnum, *) to port number. 🧹 cleanup era

void svcerr_auth(SVCXPRT *xprt, enum auth_stat why)

Called by a service dispatch routine that refuses to perform a remote procedure call due to an authentication error. 🙈 not the auth fail

void svcerr_decode(SVCXPRT *xprt)

Called by a service dispatch routine that cannot successfully decode its arguments. See also svc_getargs(). 😭

void svcerr_noproc(SVCXPRT *xprt)

Called by a service dispatch routine that does not implement the procedure number that the caller requests. bestie that proc doesn't exist 💀

void svcerr_noprog(SVCXPRT *xprt)

Called when the desired program is not registered with the RPC package. Service implementors usually do not need this routine. 👑

void svcerr_progvers(SVCXPRT *xprt, u_long low_vers, u_long high_vers)

Called when the desired version of a program is not registered with the RPC package. Service implementors usually do not need this routine. 🦋

void svcerr_systemerr(SVCXPRT *xprt)

Called by a service dispatch routine when it detects a system error not covered by any particular protocol. For example, if a service can no longer allocate storage, it may call this routine. 🔥

void svcerr_weakauth(SVCXPRT *xprt)

Called by a service dispatch routine that refuses to perform a remote procedure call due to insufficient authentication arguments. The routine calls svcerr_auth(xprt, AUTH_TOOWEAK). 💅 weak auth? in this economy?

SVCXPRT *svcraw_create(void)

This routine creates a toy RPC service transport, to which it returns a pointer. 🎀 The transport is really a buffer within the process's address space, so the corresponding RPC client should live in the same address space; see clntraw_create(). This routine allows simulation of RPC and acquisition of RPC overheads (such as round trip times), without any kernel interference. ⭐ This routine returns NULL if it fails.

SVCXPRT *svctcp_create(int sock, u_int send_buf_size, u_int recv_buf_size)

This routine creates a TCP/IP-based RPC service transport, to which it returns a pointer. 🌈 The transport is associated with the socket sock, which may be RPC_ANYSOCK, in which case a new socket is created. If the socket is not bound to a local TCP port, then this routine binds it to an arbitrary port. Upon completion, xprt->xp_fd is the transport's socket descriptor, and xprt->xp_port is the transport's port number. This routine returns NULL if it fails.

Since TCP-based RPC uses buffered I/O, users may specify the size of buffers; values of zero choose suitable defaults. 🫶

SVCXPRT *svcunix_create(int sock, u_int send_buf_size, u_int recv_buf_size, char *path)

This routine creates a Unix-based RPC service transport, to which it returns a pointer. 🌸 The transport is associated with the socket sock, which may be RPC_ANYSOCK, in which case a new socket is created. The *path argument is a variable-length file system pathname of at most 104 characters. 😳

Heads up bestie: this file is not removed when the socket is closed. The unlink(2) system call must be used to remove the file. Periodt. 💀

Upon completion, xprt->xp_fd is the transport's socket descriptor. This routine returns NULL if it fails. Since Unix-based RPC uses buffered I/O, users may specify the size of buffers; values of zero choose suitable defaults. ✨

SVCXPRT *svcunixfd_create(int fd, u_int sendsize, u_int recvsize)

Create a service on top of any open descriptor. The sendsize and recvsize arguments indicate sizes for the send and receive buffers. If they are zero, a reasonable default is chosen. 💖

SVCXPRT *svcfd_create(int fd, u_int sendsize, u_int recvsize)

Create a service on top of any open descriptor. Typically, this descriptor is a connected socket for a stream protocol such as TCP. The sendsize and recvsize arguments indicate sizes for the send and receive buffers. If they are zero, a reasonable default is chosen. 🧚

SVCXPRT *svcudp_bufcreate(int sock, u_int sendsize, u_int recvsize)

This routine creates a UDP/IP-based RPC service transport, to which it returns a pointer. 🌈 The transport is associated with the socket sock, which may be RPC_ANYSOCK, in which case a new socket is created. If the socket is not bound to a local UDP port, then this routine binds it to an arbitrary port. Upon completion, xprt->xp_fd is the transport's socket descriptor, and xprt->xp_port is the transport's port number. This routine returns NULL if it fails.

This allows the user to specify the maximum packet size for sending and receiving UDP-based RPC messages. 📦

bool_t xdr_accepted_reply(XDR *xdrs, struct accepted_reply *ar)

Used for encoding RPC reply messages. This routine is useful for users who wish to generate RPC-style messages without using the RPC package. 👑

bool_t xdr_authunix_parms(XDR *xdrs, struct authunix_parms *aupp)

Used for describing Unix credentials. This routine is useful for users who wish to generate these credentials without using the RPC authentication package. 🎀

void
bool_t xdr_callhdr(XDR *xdrs, struct rpc_msg *chdr)

Used for describing RPC call header messages. This routine is useful for users who wish to generate RPC-style messages without using the RPC package. ✨

bool_t xdr_callmsg(XDR *xdrs, struct rpc_msg *cmsg)

Used for describing RPC call messages. This routine is useful for users who wish to generate RPC-style messages without using the RPC package. 💅

bool_t xdr_opaque_auth(XDR *xdrs, struct opaque_auth *ap)

Used for describing RPC authentication information messages. This routine is useful for users who wish to generate RPC-style messages without using the RPC package. 🦋

struct pmap;
bool_t xdr_pmap(XDR *xdrs, struct pmap *regs)

Used for describing arguments to various rpcbind(8) procedures, externally. This routine is useful for users who wish to generate these arguments without using the pmap_*() interface. ⭐

bool_t xdr_pmaplist(XDR *xdrs, struct pmaplist **rp)

Used for describing a list of port mappings, externally. This routine is useful for users who wish to generate these arguments without using the pmap_*() interface. 📋

bool_t xdr_rejected_reply(XDR *xdrs, struct rejected_reply *rr)

Used for describing RPC reply messages. This routine is useful for users who wish to generate RPC-style messages without using the RPC package. 🙈

bool_t xdr_replymsg(XDR *xdrs, struct rpc_msg *rmsg)

Used for describing RPC reply messages. This routine is useful for users who wish to generate RPC style messages without using the RPC package. 💜

void xprt_register(SVCXPRT *xprt)

After RPC service transport handles are created, they should register themselves with the RPC service package. This routine modifies the global variable svc_fds. Service implementors usually do not need this routine. 🫶

void xprt_unregister(SVCXPRT *xprt)

Before an RPC service transport handle is destroyed, it should unregister itself with the RPC service package. This routine modifies the global variable svc_fds. Service implementors usually do not need this routine. 🧹

🔗 SEE ALSO 🔗

rpc_secure(3), xdr(3)

Remote Procedure Calls: Protocol Specification.

Remote Procedure Call Programming Guide.

rpcgen Programming Guide.

RPC: Remote Procedure Call Protocol Specification, Sun Microsystems, Inc., USC-ISI, RFC1050.

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📦 where this page comes from

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RPC_SOC(3)

💅 RPC_SOC(3) — library routines for remote procedure calls ✨

✨ NAME ✨

🫶 LIBRARY 🫶

🌸 SYNOPSIS 🌸

🦋 DESCRIPTION 🦋

🎀 auth_destroy

🌈 authnone_create

🍓 authunix_create

🧚 authunix_create_default

🔥 callrpc

🌟 clnt_broadcast

💜 clnt_call

🦋 clnt_destroy

👑 clnt_create

💅 clnt_control

🎀 clnt_freeres

🌸 clnt_geterr

🫶 clnt_pcreateerror

⭐ clnt_perrno

🍓 clnt_perror

🧚 clnt_spcreateerror

🌈 clnt_sperrno

💜 clnt_sperror

🧸 CLIENT *clntraw_create(u_long prognum, u_long versnum)

🌐 CLIENT *clnttcp_create(...)

📨 CLIENT *clntudp_create(...)

📦 CLIENT *clntudp_bufcreate(...)

🦋 CLIENT *clntunix_create(...)

🏠 int get_myaddress(struct sockaddr_in *addr)

🗺️ struct pmaplist *pmap_getmaps(struct sockaddr_in *addr)

🔍 u_short pmap_getport(...)

📡 enum clnt_stat pmap_rmtcall(...)

📌 bool_t pmap_set(...)

🧹 bool_t pmap_unset(u_long prognum, u_long versnum)

📝 bool_t registerrpc(...)

🚨 struct rpc_createerr rpc_createerr;

💥 bool_t svc_destroy(SVCXPRT *xprt)

🎛️ fd_set svc_fdset;

🕰️ int svc_fds;

🗑️ bool_t svc_freeargs(SVCXPRT *xprt, xdrproc_t inproc, char *in)

🎁 bool_t svc_getargs(SVCXPRT *xprt, xdrproc_t inproc, char *in)

📞 struct sockaddr_in *svc_getcaller(SVCXPRT *xprt)

🔔 void svc_getreqset(fd_set *rdfds)

🔁 void svc_getreq(int rdfds)