


INTRO(1)	    UNIX Programmer's Manual		 INTRO(1)



NAME
     intro - introduction to commands

DESCRIPTION
     This section describes publicly accessible commands in
     alphabetic order.	Certain distinctions of purpose are made
     in the headings:

     (1)  Commands of general utility.

     (1C) Commands for communication with other systems.

     (1G) Commands used primarily for graphics and computer-aided
	  design.

     N.B.: Commands related to system maintenance used to appear
     in section 1 manual pages and were distinguished by (1M) at
     the top of the page.  These manual pages now appear in sec-
     tion 8.

SEE ALSO
     Section (6) for computer games.

     _H_o_w _t_o _g_e_t _s_t_a_r_t_e_d, in the Introduction.

DIAGNOSTICS
     Upon termination each command returns two bytes of status,
     one supplied by the system giving the cause for termination,
     and (in the case of `normal' termination) one supplied by
     the program, see _w_a_i_t and _e_x_i_t(2).  The former byte is 0 for
     normal termination, the latter is customarily 0 for success-
     ful execution, nonzero to indicate troubles such as errone-
     ous parameters, bad or inaccessible data, or other inability
     to cope with the task at hand.  It is called variously `exit
     code', `exit status' or `return code', and is described only
     where special conventions are involved.



















Printed 11/26/99	 April 29, 1985                         1



