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wfix + ffix

This commit is contained in:
Michael Kerrisk 2007-05-28 10:45:57 +00:00
parent f11e5e44f7
commit 6602f61c23
1 changed files with 24 additions and 23 deletions
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47
man3/getnameinfo.3
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@ -181,52 +181,53 @@ In order to assist the programmer in choosing reasonable sizes
for the supplied buffers, for the supplied buffers,
.I <netdb.h> .I <netdb.h>
defines the constants defines the constants
.RS .in +0.5i
.nf .nf
# define NI_MAXHOST 1025 # define NI_MAXHOST 1025
.br
# define NI_MAXSERV 32 # define NI_MAXSERV 32
.fi .fi
.RE .in
.PP
The former is the constant MAXDNAME in recent versions of BIND's The former is the constant MAXDNAME in recent versions of BIND's
.I <arpa/nameser.h> .I <arpa/nameser.h>
header file. header file.
The latter is a guess based on the services listed The latter is a guess based on the services listed
in the current Assigned Numbers RFC. in the current Assigned Numbers RFC.
.SH EXAMPLE .SH EXAMPLE
The following code tries to get the numeric hostname and service name, for The following code tries to get the numeric hostname and service name,
a given socket address. for a given socket address.
Note that there is no hardcoded reference to Note that there is no hardcoded reference to
a particular address family. a particular address family.
.RS .in +0.5i
.nf .nf
struct sockaddr *sa; /* input */ struct sockaddr *sa; /* input */
char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), sbuf, if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), sbuf,
sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV) == 0) sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV) == 0)
printf("host=%s, serv=%s\en", hbuf, sbuf); printf("host=%s, serv=%s\en", hbuf, sbuf);
.fi .fi
.RE .in
The following version checks if the socket address has a The following version checks if the socket address has a
reverse address mapping. reverse address mapping.
.RS .in +0.5i
.fi .nf
struct sockaddr *sa; /* input */ struct sockaddr *sa; /* input */
char hbuf[NI_MAXHOST]; char hbuf[NI_MAXHOST];
if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf),
NULL, 0, NI_NAMEREQD)) NULL, 0, NI_NAMEREQD))
printf("could not resolve hostname"); printf("could not resolve hostname");
else else
printf("host=%s\en", hbuf); printf("host=%s\en", hbuf);
.fi .fi
.RE .in
.PP .PP
An example program use An example program using
.BR getnameinfo () .BR getnameinfo ()
can be found in can be found in
.BR getaddrinfo (3). .BR getaddrinfo (3).