errcatch — error trapping
errcatch(n [,'action'] [,'option']) errcatch()
errcatch gives an "action" (error-handler) to be
performed when an error of type n occurs.
n has the following meaning:
if n>0, n is the error number to trap
if n<0 all errors are to be trapped
action is one of the following character strings:
a pause is executed when trapping the error. This option is
useful for debugging purposes. Use whereami() to get information
on the current context.
next instruction in the function or exec files is executed,
current instruction is ignored. It is possible to check if an error has occured
using the iserror function. Do not forget to clear the error using
the errclear function as soon as possible This option is useful
for error recovery. In many cases, usage of
errcatch(n,"continue",..) can be replaced by the use of
execstr function or try control structure.
default mode, all intermediate functions are killed, scilab goes back to the level 0 prompt.
interrupts the current Scilab session (useful when Scilab is called from an external program).
option is the character string 'nomessage' for killing
error message.
To set back default mode, enter errcatch(-1,"kill") or similarly
errcatch(-1).errcatch() is an obsolete equivalent of errcatch(-1).
The errcatch actions apply to the current evalution
context (function, exec, pause ) and all the sub-levels. A second
errcatch call in a sub-level hides the initial one for
this sub-level. If a second errcatch call is made at the
same level, the effect of the first one is removed.
When called in the context of a Scilab function or exec the errcatch is automatically
reset when the function returns.