trycatch

Scilab keyword
Last update : 30/08/2005

try - beginning of try block in try-catch control instruction

catch - beginning of catch block in try-catch control instruction

### Calling Sequence

  `try`
  `statements`
  `catch`
  `statements`
  `end`

### Description

The `try`-`catch` control instruction can be used to manage codes that could possibly generate errors.

When a `try`-`catch` control instruction is executed, normally only the statements between the `try` and `catch` keywords are executed. However, if an error occurs during execution of any of these statements, the error is recorded, the remaining statements up to the `catch` keyword are skipped and the statements between the `catch` and `end` keywords are executed using the default error handling mode (see: `errcatch`.

The recorded error can be retreived using the `lasterror` function.

The `catch` statements as well as the `catch` keyword can be omitted if no alternative statements are given.

Note that one can also use the `execstr` function with `'errcatch'` argument for error handling. This can be particularily useful for handling syntactical errors.

### Examples

     file_path=TMPDIR+'/wrong'
     try
        u=mopen(file_path,'r')
        x=mget(10,'c',u)
      catch
        disp(['file '+file_path+ 'cannot be read',
              'using default values for x'])
        x=1:10
      end
      [error_message,error_number]=lasterror(%t)

### See Also

`error`, `execstr`, `if`, `lasterror`, `errcatch`,

### Author

Serge Steer, INRIA