sethostent()--Open Host Database

 #include <netdb.h>

 void sethostent(int stay_open)

The sethostent() function is used to prepare for sequential access to the host database file. sethostent() opens the file and repositions the file marker to the beginning of the file. In addition, sethostent() affects what type of transport service (connectionless versus connection-oriented) is to be used when gethostbyname() and gethostbyaddr() need to retrieve host information from the domain name server.

Parameters

int stay_open

(Input) Specifies whether to leave the database file open after each call to gethostbyname() and gethostbyaddr(). A nonzero value results in the database file being left open. Also, a nonzero value results in the use of a connection-oriented transport service (for example, TCP) being used by gethostbyname() and gethostbyaddr() when host information is to be obtained from the domain name server.

Authorities

No authorization is required.

Error Conditions

When sethostent() fails, h_errno (defined in <netdb.h>) can be set to one of the following:

NO_RECOVERY

An unrecoverable error has occurred.

Usage Notes

1. The iSeries Navigator or the following CL commands can be used to access the host database file:
   
   
   • ADDTCPHTE (Add TCP/IP Host Table Entry
   • RMVTCPHTE (Remove TCP/IP Host Table Entry)
   • CHGTCPHTE (Change TCP/IP Host Table Entry)
   • RNMTCPHTE (Rename TCP/IP Host Table Entry)
   • MRGTCPHT (Merge TCP/IP Host Tables)
   
   
2. Do not use the sethostent() function in a multithreaded environment. See the multithread alternative sethostent_r() function.
   
   
3. When you develop in C-based languages and an application is compiled with the _XOPEN_SOURCE macro defined to the value 520 or greater, the sethostent() API is mapped toqso_sethostent98().

Related Information

• _XOPEN_SOURCE--Using _XOPEN_SOURCE for the UNIX 98 compatible interface
  
  
• gethostbyaddr()--Get Host Information for IP Address
  
  
• gethostbyname()--Get Host Information for Host Name
  
  
• endhostent()--Close Host Database
  
  
• gethostent()--Get Next Entry from Host Database