limits(5)							File Formats Manual							 limits(5)

NAME

       limits - implementation-specific constants

SYNOPSIS

DESCRIPTION

       The  following symbols are defined in and are used throughout the descriptive text of this manual.  The column headed HP-UX Value lists the
       values that application writers should assume for portability across all HP-UX systems.

       Symbols after values are interpreted as follows:

	      Actual limit might be greater than specified value on certain
		   HP-UX systems.

	      Actual limit might be greater than value specified in
		   on certain HP-UX systems.

	      Actual limit might be less than the specified value on certain
		   HP-UX systems.

	      Actual limit is always equal to the specified value
		   and does not vary across HP-UX systems.

	      The name of this limit is defined
		   if the preprocessor macro is defined, either by the compilation flag or by a directive in the source before is included in  the
		   source.

	      The value defined for this limit might not be a compile-time constant.
		   The value defined always evaluates to an integer expression at run time.

       Some  of  these limits vary with system configuration, and can be determined dynamically by using sysconf(2).  Others can vary according to
       file system or device associated with a specific file, and can be determined with pathconf(2).  Others are  obsolescent	because  they  are
       redundant  with	other  limits or not useful in portable applications.  They are provided only for importability of applications from other
       systems, to support applications that comply with the and for backward compatibility with earlier versions of HP-UX.  The flag  should  not
       be defined in new applications.

       By including the file in the compilation an application can test the appropriate limits to determine whether it can operate on a particular
       system, or it might even alter its behavior to match the system to increase its portability across a varying range of  limit  settings  and
       systems.

       Constant    Description				       HP-UX Value
       --------------------------------------------------------------------
       ARG_MAX	   Max	length	of arguments to 		   5120 +*
		   exec(2) in bytes,  including
		   environment data
       CHAR_BIT    Number of bits in a				       8 =
       CHAR_MAX    Max integer value of a			     127 =
       CHAR_MIN    Min integer value of a			    -128 =
       CHILD_MAX   Max	number	of simultaneous 		    25 +-*
		   processes per user ID
       CLK_TCK	   Number of  clock  ticks  per 		     50 +#
		   second
       DBL_DIG	   Digits of precision of a			      15 +
       DBL_MAX	   Max positive value of a	 1.7976931348623157e+308 +
       DBL_MIN	   Min positive value of a	4.94065645841246544e-324 -
       FCHR_MAX    Max file offset in bytes		       INT_MAX +-*
       FLT_DIG	   Digits of precision of a			       6 +
       FLT_MAX	   Max positive value of a	 3.40282346638528860e+38 +
       FLT_MIN	   Min positive value of a	 1.40129846432481707e-45 -
       INT_MAX	   Max decimal value of an		      2147483647 +
       INT_MIN	   Min decimal value of an		     -2147483648 -

       LINE_MAX    Max	number of characters in 		    2048 =
		   a single line
       LINK_MAX    Max number  of  links  to  a 		  32767 +*
		   single file
       LOCK_MAX    Max	number	of  entries  in 		    32 +-*
		   system lock table
       LONG_BIT    Number of bits in a				      32 +
       LONG_MAX    Max decimal value of a		      2147483647 +
       LONG_MIN    Min decimal value of a		     -2147483648 -
       MAX_CANON   Max number of bytes in  ter- 		    512 +*
		   minal canonical input line
       MAX_CHAR    Max	number of bytes in ter- 	      MAX_INPUT =*
		   minal input queue
       MAX_INPUT   Max number of bytes in  ter- 		    512 +*
		   minal input queue
       NAME_MAX    Max	number	of  bytes  in a 		     14 +*
		   path name component
       NL_ARGMAX   Max	value  of  "digits"  in 		       9 =
		   calls  to the NLS printf(3S)
		   and scanf(3S) functions
       NL_MSGMAX   Max message number in an NLS 		   32767 +
		   message catalog
       NL_SETMAX   Max	set  number  in  an NLS 		     255 +
		   message catalog
       NL_TEXTMAX  Max number of  bytes  in  an 		    8192 +
		   NLS message string
       NGROUPS_MAX Max	number of supplementary 		     20 ++
		   groups per process
       OPEN_MAX    Max	number	 of   files   a 		     60 +*
		   process can have open
       PASS_MAX    Max	number	of  chars  in a 		       8 +
		   password
       PATH_MAX    Max number of characters  in 		   1023 +*
		   a  path  name  excluding the
		   null terminator
       PID_MAX	   Max value for a process ID			   30000 +
       PIPE_BUF    Max number of  bytes  atomic 		   8192 +*
		   in write to a pipe
       PIPE_MAX    Max number of bytes writable 		 INT_MAX +
		   to a pipe in one write
       PROC_MAX    Max number  of  simultaneous 		    84 +-*
		   processes on system
       SCHAR_MAX   Max integer value of a			     127 =
       SCHAR_MIN   Min integer value of a			    -128 =
       SHRT_MAX    Max decimal value of a			   32767 +
       SHRT_MIN    Min decimal value of a			  -32768 -
       STD_BLK	   Number  of bytes in a physi- 		     512 +
		   cal I/O block
       SYSPID_MAX  Max	process  ID  of  system 		     4 +-*
		   processes
       SYS_NMLN    Length  of  strings returned 		      8 +*
		   by uname(2)
       SYS_OPEN    Max number of files open  on 		   120 +-*
		   system
       TMP_MAX	   Max	number	of unique names 		   17576 +
		   generated by tmpnam(3S)
       UCHAR_MAX   Max integer value of an			     255 =
       UID_MAX	   Smallest unattainable  value 	      2147483647 +
		   for a user or group ID
       UINT_MAX    Max decimal value of an		      4294967295 +
       ULONG_MAX   Max decimal value of an		      4294967295 +
       USHRT_MAX   Max decimal value of an			   65535 +
       USI_MAX	   Max decimal value of an		       UINT_MAX =*
       WORD_BIT    Number of bits in a "word"			      32 +

EXAMPLES

       has  an HP-UX value of which means that on all HP-UX systems the smallest unattainable value for a user or group ID is at least 2147483647.
       A particular system might be capable of supporting more than 2147483647 user or group IDs, in which case its file sets to a  higher  value;
       however, any application assuming such a higher value is not guaranteed to be portable to all HP-UX systems.

       has an HP-UX value of which means that on all HP-UX systems the smallest maximum number of supplementary groups per process is at least 20.
       A particular system might be capable of supporting more than 20 supplementary groups per process, in which case will return a larger  value
       than that specified in however, any application assuming such a higher value is not guaranteed to be portable to all HP-UX systems.

AUTHOR

       limits was developed by HP.

SEE ALSO

       exec(2),  fcntl(2),  fork(2), getgroups(2), link(2), lockf(2), open(2), pathconf(2), sysconf(2), uname(2), write(2), printf(3S), scanf(3S),
       tmpnam(3S), passwd(4), values(5), termio(7).

STANDARDS CONFORMANCE

																	 limits(5)