newgrp.tproj/newgrp.1

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  27 .Dd May 23, 2002
  28 .Dt NEWGRP 1
  29 .Os
  30 .Sh NAME
  31 .Nm newgrp
  32 .Nd change to a new group
  33 .Sh SYNOPSIS
  34 .Nm
  35 .Op Fl l
  36 .Op Ar group
  37 .Sh DESCRIPTION
  38 The
  39 .Nm
  40 utility creates a new shell execution environment with modified
  41 real and effective group IDs.
  42 .Pp
  43 The options are as follows:
  44 .Bl -tag -width indent
  45 .It Fl l
  46 Simulate a full login.
  47 The environment and umask are set to what would be expected if the user
  48 actually logged in again.
  49 .El
  50 .Pp
  51 If the
  52 .Ar group
  53 operand is present, a new shell is started with the specified effective
  54 and real group IDs.
  55 The user will be prompted for a password if they are not a member of the
  56 specified group.
  57 .Pp
  58 Otherwise, the real, effective and supplementary group IDs are restored to
  59 those from the current user's password database entry.
  60 .Sh EXIT STATUS
  61 The
  62 .Nm
  63 utility attempts to start the shell regardless of whether group IDs
  64 were successfully changed.
  65 .Pp
  66 If an error occurs and the shell cannot be started,
  67 .Nm
  68 exits >0.
  69 Otherwise, the exit status of
  70 .Nm
  71 is the exit status of the shell.
  72 .Sh SEE ALSO
  73 .Xr csh 1 ,
  74 .Xr groups 1 ,
  75 .Xr login 1 ,
  76 .Xr sh 1 ,
  77 .Xr su 1 ,
  78 .Xr umask 1 ,
  79 .Xr group 5 ,
  80 .Xr passwd 5 ,
  81 .Xr environ 7
  82 .Sh STANDARDS
  83 The
  84 .Nm
  85 utility conforms to
  86 .St -p1003.1-2001 .
  87 .Sh HISTORY
  88 A
  89 .Nm
  90 utility appeared in
  91 .At v6 .
  92 .Sh BUGS
  93 Group passwords are inherently insecure as there is no way to stop
  94 users obtaining the crypted passwords from the group database.
  95 Their use is discouraged.