getsvc.3

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 3 代码 · 共 104 行

./" new manpage created for FT2 of V4.0       20 dec, 1989  (JM)
.TH getsvc 3
.SH Name
getsvc - get a pointer to the svcinfo structure
.SH Syntax
.B #include <sys/svcinfo.h>
.PP
.B struct svcinfo *getsvc()
.SH Description
.NXR "getsvc call"
.PP
The 
.PN getsvc 
call retrieves information from the system about the
.PN svcinfo 
structure by returning a pointer to the structure.  This
structure is initialized the first time a 
.PN getsvc 
call is made.  The
contents of the 
.PN /etc/svc.conf 
file are parsed and stored in the
.PN svcinfo 
structure.  If the 
.PN /etc/svc.conf 
file is modified, the
contents of this structure will be updated upon the next 
.PN getsvc 
call.
.PP
The 
.PN /etc/svc.conf 
file contains the names of the databases that can be
served by YP, BIND, or local files and the name service selection for
each database.  It also has settings for four security parameters.
The database service selection and security parameters are stored
in the 
.PN svcinfo
structure.
.PP
The following structure exists in the 
.PN svcinfo.h
file:
.EX 
#define SVC_DATABASES 20
#define SVC_PATHSIZE 8
struct svcinfo {
    int svcdate;       /* Last mod date of /etc/svc.conf */

    int svcpath[SVC_DATABASES][SVC_PATHSIZE];    /* indexed by
                          databases and choice 0=first choice
	                  1=second choice, etc value stored is
			  source */

       struct {
           int passlenmin;
           int passlenmax;
           int softexp;
           int seclevel;
       } svcauth;
};
.EE
.PP 
The 
.PN svcdate 
field contains the date that the 
.PN /etc/svc.conf 
file was last modified.  The 
.PN svcpath 
array contains the name service choices for each database.  The 
.PN svcauth 
structure contains the values for the four security parameters:  
password length minimum (\fIpasslenmin\fR), password length maximum
(\fIpasslenmax\fR), soft expiration date of a password (\fIsoftexp\fR),
and security mode of a system (\fIseclevel\fR).
.SH Examples
The following programming example shows how to use the
.PN getsvc
call to use the information in the 
.PN svcinfo 
structure to process specific
host information.
.EX
#include <sys/svcinfo.h> 
struct svcinfo *svcinfo;

if ((svcinfo = getsvc()) != NULL)
  for (i=0; (j = svcinfo->svcpath[SVC_HOSTS][i]) != SVC_LAST; i++)
	 switch(j) {
	     case SVC_BIND:
	         /* process BIND hosts */
	     case SVC_YP:
	         /* process YP hosts */
	     case SVC_LOCAL:
		 /* process LOCAL hosts */
	 }
.EE
.SH Files
.PN /etc/svc.conf
.br
.PN /usr/include/sys/svcinfo.h
.SH See Also
svc.conf(5), svcsetup(8)