EnvVar                 package:base                 R Documentation

_E_n_v_i_r_o_n_m_e_n_t _V_a_r_i_a_b_l_e_s

_D_e_s_c_r_i_p_t_i_o_n:

     Details of some of the environment variables which affect an R
     session.

_D_e_t_a_i_l_s:

     It is impossible to list all the environment variables which can
     affect an R session: some affect the OS system functions which R
     uses, and others will affect add-on packages.  But here are notes
     on some of the more important ones.

     '_H_O_M_E': The user's 'home' directory.

     '_L_A_N_G_U_A_G_E': Optional.  The language(s) to be used for message
          translations.

     '_L_C__A_L_L': (etc) Optional.  Use to set various aspects of the
          locale - see 'Sys.getlocale'.

     '_R__B_A_T_C_H': Optional - set in a batch session.

     '_R__C_O_M_P_L_E_T_I_O_N': Optional.  If set to 'FALSE', comand-line
          completion is not used.  (Not used by Mac OS GUI.)

     '_R__D_E_F_A_U_L_T__P_A_C_K_A_G_E_S': A comma-separated list of packages which are
          to be loaded in every session.  See 'options'.

     '_R__E_N_V_I_R_O_N': Optional.  The path to the site environment file: see
          Startup.

     '_R__G_S_C_M_D': Optional.  The path to GhostScript.

     '_R__H_I_S_T_F_I_L_E': Optional.  The path of the history file: see
          Startup.

     '_R__H_I_S_T_S_I_Z_E': Optional.  The maximum size of the history file, in
          lines.

     '_R__H_O_M_E': The top-level directory of the R installation.  Set by
          R.

     '_R__L_I_B_S': Optional.  Setting for '.libPaths'.

     '_R__L_I_B_S__S_I_T_E': Optional.  Setting for '.libPaths'.

     '_R__L_I_B_S__U_S_E_R': Optional.  Setting for '.libPaths'.

     '_R__P_A_P_E_R_S_I_Z_E': Optional.  The default papersize, e.g. for 'pdf'
          and 'postscript'.

     '_R__P_R_O_F_I_L_E': Optional.  The path to the site profile file: see
          Startup.

     '_R__R_D_4_D_V_I': Options for 'latex' processing of 'Rd' files.

     '_R__R_D_4_P_D_F': Options for 'pdflatex' processing of 'Rd' files.

     '_T_M_P_D_I_R', '_T_M_P', '_T_E_M_P': Consulted (in that order) when setting
          the temporary directory.  See 'tempdir'.

     '_T_Z': Optional. The current timezone.  See 'as.POSIXlt' for the
          system-specific formats.

     '_n_o__p_r_o_x_y', '_h_t_t_p__p_r_o_x_y', '_f_t_p__p_r_o_x_y': (and more).  Optional. 
          Settings for 'download.file'.

_U_n_i_x-_s_p_e_c_i_f_i_c:

     Some variables set on Unix-alikes, and not (in general) on
     Windows.

     '_D_I_S_P_L_A_Y': Optional: used by 'X11', Tk (in package 'tcltk'), the
          data editor and various packages.

     '_E_D_I_T_O_R': The path to default editor.

     '_P_A_G_E_R': The path to default pager.

     '_R__B_R_O_W_S_E_R': The path to default browser.

     '_R__D_O_C__D_I_R': The location of the R 'doc' directory.

     '_R__D_V_I_P_S_C_M_D': The path to 'dvips'.

     '_R__I_N_C_L_U_D_E__D_I_R': The location of the R 'include' directory.

     '_R__L_A_T_E_X_C_M_D': The path to 'latex'.

     '_R__M_A_K_E_I_N_D_E_X_C_M_D': The path to 'makeindex'.

     '_R__P_D_F_V_I_E_W_E_R': The path to default PDF viewer.

     '_R__P_L_A_T_F_O_R_M': The platform - a string of the form 'cpu-vendor-os',
          see 'R.Version'.

     '_R__P_R_I_N_T_C_M_D': Print command to be used by 'postscript'.

     '_R__S_H_A_R_E__D_I_R': The location of the R 'share' directory. 

     '_R__U_N_Z_I_P_C_M_D': The path to 'unzip'.

     '_R__Z_I_P_C_M_D': The path to 'zip'.

_S_e_e _A_l_s_o:

     'Sys.getenv' and 'Sys.setenv' to read and set environmental
     variables in an R session.

