gawk: Other Environment Variables

1 
1 2.5.3 Other Environment Variables
1 ---------------------------------
1 
1 A number of other environment variables affect 'gawk''s behavior, but
1 they are more specialized.  Those in the following list are meant to be
1 used by regular users:
1 
1 'GAWK_MSEC_SLEEP'
1      Specifies the interval between connection retries, in milliseconds.
1      On systems that do not support the 'usleep()' system call, the
1      value is rounded up to an integral number of seconds.
1 
1 'GAWK_READ_TIMEOUT'
1      Specifies the time, in milliseconds, for 'gawk' to wait for input
1      before returning with an error.  ⇒Read Timeout.
1 
1 'GAWK_SOCK_RETRIES'
1      Controls the number of times 'gawk' attempts to retry a two-way
DONTPRINTYET 11      TCP/IP (socket) connection before giving up.  ⇒TCP/IP
      Networking.  Note that when nonfatal I/O is enabled (*note1DONTPRINTYET 11      TCP/IP (socket) connection before giving up.  ⇒TCP/IP
      Networking.  Note that when nonfatal I/O is enabled (⇒
      Nonfatal), 'gawk' only tries to open a TCP/IP socket once.
1 
1 'POSIXLY_CORRECT'
1      Causes 'gawk' to switch to POSIX-compatibility mode, disabling all
1      traditional and GNU extensions.  ⇒Options.
1 
1    The environment variables in the following list are meant for use by
1 the 'gawk' developers for testing and tuning.  They are subject to
1 change.  The variables are:
1 
1 'AWKBUFSIZE'
1      This variable only affects 'gawk' on POSIX-compliant systems.  With
1      a value of 'exact', 'gawk' uses the size of each input file as the
1      size of the memory buffer to allocate for I/O. Otherwise, the value
1      should be a number, and 'gawk' uses that number as the size of the
1      buffer to allocate.  (When this variable is not set, 'gawk' uses
1      the smaller of the file's size and the "default" blocksize, which
1      is usually the filesystem's I/O blocksize.)
1 
1 'AWK_HASH'
1      If this variable exists with a value of 'gst', 'gawk' switches to
1      using the hash function from GNU Smalltalk for managing arrays.
1      This function may be marginally faster than the standard function.
1 
1 'AWKREADFUNC'
1      If this variable exists, 'gawk' switches to reading source files
1      one line at a time, instead of reading in blocks.  This exists for
1      debugging problems on filesystems on non-POSIX operating systems
1      where I/O is performed in records, not in blocks.
1 
1 'GAWK_MSG_SRC'
1      If this variable exists, 'gawk' includes the file name and line
1      number within the 'gawk' source code from which warning and/or
1      fatal messages are generated.  Its purpose is to help isolate the
1      source of a message, as there are multiple places that produce the
1      same warning or error message.
1 
1 'GAWK_LOCALE_DIR'
1      Specifies the location of compiled message object files for 'gawk'
1      itself.  This is passed to the 'bindtextdomain()' function when
1      'gawk' starts up.
1 
1 'GAWK_NO_DFA'
1      If this variable exists, 'gawk' does not use the DFA regexp matcher
1      for "does it match" kinds of tests.  This can cause 'gawk' to be
1      slower.  Its purpose is to help isolate differences between the two
1      regexp matchers that 'gawk' uses internally.  (There aren't
1      supposed to be differences, but occasionally theory and practice
1      don't coordinate with each other.)
1 
1 'GAWK_STACKSIZE'
1      This specifies the amount by which 'gawk' should grow its internal
1      evaluation stack, when needed.
1 
1 'INT_CHAIN_MAX'
1      This specifies intended maximum number of items 'gawk' will
1      maintain on a hash chain for managing arrays indexed by integers.
1 
1 'STR_CHAIN_MAX'
1      This specifies intended maximum number of items 'gawk' will
1      maintain on a hash chain for managing arrays indexed by strings.
1 
1 'TIDYMEM'
1      If this variable exists, 'gawk' uses the 'mtrace()' library calls
1      from the GNU C library to help track down possible memory leaks.
1