projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 931a9d50 C |
1 | .TH GETHOSTENT 3N "9 February 1983" |
| 2 | .UC 4 | |
| 3 | .SH NAME | |
| 4 | gethostent, gethostbyaddr, gethostbyname, sethostent, endhostent \- get network host entry | |
| 5 | .SH SYNOPSIS | |
| 6 | .B "#include <netdb.h> | |
| 7 | .PP | |
| 8 | .B "struct hostent *gethostent() | |
| 9 | .PP | |
| 10 | .B "struct hostent *gethostbyname(name) | |
| 11 | .br | |
| 12 | .B "char *name; | |
| 13 | .PP | |
| 14 | .B "struct hostent *gethostbyaddr(addr, len, type) | |
| 15 | .br | |
| 16 | .B "char *addr; int len, type; | |
| 17 | .PP | |
| 18 | .B "sethostent(stayopen) | |
| 19 | .br | |
| 20 | .B "int stayopen | |
| 21 | .PP | |
| 22 | .B "endhostent() | |
| 23 | .SH DESCRIPTION | |
| 24 | .IR Gethostent , | |
| 25 | .IR gethostbyname , | |
| 26 | and | |
| 27 | .I gethostbyaddr | |
| 28 | each return a pointer to an object with the | |
| 29 | following structure | |
| 30 | containing the broken-out | |
| 31 | fields of a line in the network host data base, | |
| 32 | .IR /etc/hosts . | |
| 33 | .RS | |
| 34 | .PP | |
| 35 | .nf | |
| 36 | struct hostent { | |
| 37 | char *h_name; /* official name of host */ | |
| 38 | char **h_aliases; /* alias list */ | |
| 39 | int h_addrtype; /* address type */ | |
| 40 | int h_length; /* length of address */ | |
| 41 | char *h_addr; /* address */ | |
| 42 | }; | |
| 43 | .ft R | |
| 44 | .ad | |
| 45 | .fi | |
| 46 | .RE | |
| 47 | .PP | |
| 48 | The members of this structure are: | |
| 49 | .TP \w'h_addrtype'u+2n | |
| 50 | h_name | |
| 51 | Official name of the host. | |
| 52 | .TP \w'h_addrtype'u+2n | |
| 53 | h_aliases | |
| 54 | A zero terminated array of alternate names for the host. | |
| 55 | .TP \w'h_addrtype'u+2n | |
| 56 | h_addrtype | |
| 57 | The type of address being returned; currently always AF_INET. | |
| 58 | .TP \w'h_addrtype'u+2n | |
| 59 | h_length | |
| 60 | The length, in bytes, of the address. | |
| 61 | .TP \w'h_addrtype'u+2n | |
| 62 | h_addr | |
| 63 | A pointer to the network address for the host. | |
| 64 | Host addresses are returned | |
| 65 | in network byte order. | |
| 66 | .PP | |
| 67 | .I Gethostent | |
| 68 | reads the next line of the file, opening the file if necessary. | |
| 69 | .PP | |
| 70 | .I Sethostent | |
| 71 | opens and rewinds the file. If the | |
| 72 | .I stayopen | |
| 73 | flag is non-zero, | |
| 74 | the host data base will not be closed after each call to | |
| 75 | .I gethostent | |
| 76 | (either directly, or indirectly through one of the other | |
| 77 | \*(lqgethost\*(rq calls). | |
| 78 | .PP | |
| 79 | .I Endhostent | |
| 80 | closes the file. | |
| 81 | .PP | |
| 82 | .I Gethostbyname | |
| 83 | and | |
| 84 | .I gethostbyaddr | |
| 85 | sequentially search from the beginning | |
| 86 | of the file until a matching | |
| 87 | host name or | |
| 88 | host address is found, | |
| 89 | or until EOF is encountered. | |
| 90 | Host addresses are supplied in network order. | |
| 91 | .SH FILES | |
| 92 | /etc/hosts | |
| 93 | .SH "SEE ALSO" | |
| 94 | hosts(5) | |
| 95 | .SH DIAGNOSTICS | |
| 96 | Null pointer | |
| 97 | (0) returned on EOF or error. | |
| 98 | .SH BUGS | |
| 99 | All information | |
| 100 | is contained in a static area | |
| 101 | so it must be copied if it is | |
| 102 | to be saved. Only the Internet | |
| 103 | address format is currently understood. |