gen/pwcache.3

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  32 .\"     @(#)pwcache.3   8.1 (Berkeley) 6/9/93
  33 .\" $FreeBSD: src/lib/libc/gen/pwcache.3,v 1.10 2001/10/01 16:08:51 ru Exp $
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  35 .Dd June 9, 1993
  36 .Dt PWCACHE 3
  37 .Os
  38 .Sh NAME
  39 .Nm pwcache
  40 .Nd cache password and group entries
  41 .Sh LIBRARY
  42 .Lb libc
  43 .Sh SYNOPSIS
  44 .In pwd.h
  45 .Ft char *
  46 .Fn user_from_uid "uid_t uid" "int nouser"
  47 .In grp.h
  48 .Ft char *
  49 .Fn group_from_gid "gid_t gid" "int nogroup"
  50 .Sh DESCRIPTION
  51 The
  52 .Fn user_from_uid
  53 function returns the user name associated with the argument
  54 .Fa uid .
  55 The user name is cached so that multiple calls with the same
  56 .Fa uid
  57 do not require additional calls to
  58 .Xr getpwuid 3 .
  59 If there is no user associated with the
  60 .Fa uid ,
  61 a pointer is returned
  62 to a string representation of the
  63 .Fa uid ,
  64 unless the argument
  65 .Fa nouser
  66 is non-zero, in which case a
  67 .Dv NULL
  68 pointer is returned.
  69 .Pp
  70 The
  71 .Fn group_from_gid
  72 function returns the group name associated with the argument
  73 .Fa gid .
  74 The group name is cached so that multiple calls with the same
  75 .Fa gid
  76 do not require additional calls to
  77 .Xr getgrgid 3 .
  78 If there is no group associated with the
  79 .Fa gid ,
  80 a pointer is returned
  81 to a string representation of the
  82 .Fa gid ,
  83 unless the argument
  84 .Fa nogroup
  85 is non-zero, in which case a
  86 .Dv NULL
  87 pointer is returned.
  88 .Sh SEE ALSO
  89 .Xr getgrgid 3 ,
  90 .Xr getpwuid 3
  91 .Sh HISTORY
  92 The
  93 .Fn user_from_uid
  94 and
  95 .Fn group_from_gid
  96 functions first appeared in
  97 .Bx 4.4 .