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a31078bbec
Some folks might think: “you still use RCS”?!? And we will say, hey, at least we switched from SCCS to RCS back in … I think it was around 1994 ... at least we are keeping up! :-) :-) :-) Logs say that SCCS version 18 became RCS version 19 on 1994 March 18. RCS served us well. But now it is time to move on. And so we are switching to git. Calc releases produce a lot of file changes. In the 125 releases of calc since 1996, when I started managing calc releases, there have been 15473 file mods!
79 lines
2.5 KiB
Plaintext
79 lines
2.5 KiB
Plaintext
NAME
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errno - return or set a stored error-number
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SYNOPSIS
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errno([errnum])
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TYPES
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errnum integer, 0 <= errnum <= 32767
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return integer
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DESCRIPTION
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Whenever an operation or evaluation of function returns an error-value,
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the numerical code for that value is stored as calc_errno.
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errno() returns the current value of calc_errno.
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errno(errnum) sets calc_errno to the value errnum and returns its
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previous value.
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To detect whether an error occurs during some sequence of operations,
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one may immediately before that sequence set the stored error-number
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to zero by errno(0), and then after the operations, whether or not
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an error has occurred will be indicated by errno() being nonzero or
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zero. If a non-zero value is returned, that value will be the code
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for the most recent error encountered.
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The default argument for the functions error() and strerror() is the
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currently stored error-number; in particular, if no error-value has
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been returned after the last errno(0), strerror() will return
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"No error".
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EXAMPLE
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Assuming there is no file with name "not_a_file"
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; errno(0)
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0
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; errmax(errcount()+4)
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20
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; badfile = fopen("not_a_file", "r")
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; print errno(), error(), strerror()
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2 System error 2 No such file or directory
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; a = 1/0
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; print errno(), error(), strerror()
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10001 Error 10001 Division by zero
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LIMITS
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none
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LINK LIBRARY
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none
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SEE ALSO
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errmax, errcount, error, strerror, iserror, newerror, errorcodes,
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stoponerror
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## Copyright (C) 1999-2006 Landon Curt Noll
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##
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## Calc is open software; you can redistribute it and/or modify it under
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## the terms of the version 2.1 of the GNU Lesser General Public License
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## as published by the Free Software Foundation.
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##
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## Calc is distributed in the hope that it will be useful, but WITHOUT
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## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
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## Public License for more details.
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##
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## A copy of version 2.1 of the GNU Lesser General Public License is
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## distributed with calc under the filename COPYING-LGPL. You should have
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## received a copy with calc; if not, write to Free Software Foundation, Inc.
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## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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##
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## Under source code control: 1994/10/27 03:05:08
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## File existed as early as: 1994
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##
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## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
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## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
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