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perror(3C)							    perror(3C)

       perror, errno - print system error messages

       #include	<stdio.h>

       void perror(const char *s);
       #include	<errno.h>
       int errno;

       The  perror()  function produces	a message on the standard error	output
       (file descriptor	2) describing the last error encountered during	a call
       to a system or library function.	The argument string s is printed, fol-
       lowed by	a colon	and a blank, followed by the  message  and  a  NEWLINE
       character.   If	s  is  a  null pointer or points to a null string, the
       colon is	not printed. The argument string should	include	 the  name  of
       the program that	incurred the error. The	error number is	taken from the
       external	variable errno,	which is set when errors occur but not cleared
       when non-erroneous calls	are made. See intro(2).

       In the case of multithreaded applications, the -mt option must be spec-
       ified on	the command line at compilation	time  (see  threads(5)).  When
       the  -mt	 option	 is specified, errno becomes a macro that enables each
       thread to have its own errno. This errno	macro can be  used  on	either
       side of the assignment as though	it were	a variable.

       Messages	 printed  from this function are in the	native language	speci-
       fied by the LC_MESSAGES locale category.	 See setlocale(3C).

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Interface Stability	     |Standard			   |
       |MT-Level		     |MT-Safe			   |

       intro(2), fmtmsg(3C),  gettext(3C),  setlocale(3C),  strerror(3C),  at-
       tributes(5), standards(5), threads(5)

				  31 Mar 2005			    perror(3C)


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