Perl setgrent 函数

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  描述

  setgrent 此函数将枚举设置（或重置）到组条目集的开头。该函数应在首次调用getgrent之前调用。
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  句法

  以下是此函数的简单语法-

  
  setgrent
  

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  返回值

  此函数不返回任何值。
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  示例

  以下是显示其基本用法的示例代码-

   
  while( ($name,$passwd,$gid,$members) = getgrent() ) {
     print "Name  = $name\n";
     print "Password  = $passwd\n";
     print "GID  = $gid\n";
     print "Members  = $members\n";
  }
  
  setgrent();    # Set the beginnging of the group database;
  
  print "Again reading /etc/passwd file\n";
  while( ($name,$passwd,$gid,$members) = getgrent() ) {
     print "Name  = $name\n";
     print "Password  = $passwd\n";
     print "GID  = $gid\n";
     print "Members  = $members\n";
  }
  
  endpwent;  #claose the database;
  

  尝试一下

  执行以上代码后，将产生以下结果--

  
  Name = root
  Password = x
  GID = 0
  Members = 
  Name = daemon
  Password = x
  GID = 1
  Members = 
  Name = bin
  Password = x
  GID = 2
  Members = 
  Name = sys
  Password = x
  GID = 3
  Members = 
  Name = adm
  Password = x
  GID = 4
  Members = 
  Name = tty
  Password = x
  GID = 5
  Members = 
  Name = disk
  Password = x
  GID = 6
  Members = 
  Name = lp
  Password = x
  GID = 7
  Members = 
  Name = mail
  Password = x
  GID = 8
  Members = 
  Name = news
  Password = x
  GID = 9
  Members = 
  Name = uucp
  Password = x
  GID = 10
  Members = 
  Name = man
  Password = x
  GID = 12
  Members = 
  Name = proxy
  Password = x
  GID = 13
  Members = 
  Name = kmem
  Password = x
  GID = 15
  Members = 
  Name = dialout
  Password = x
  GID = 20