diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 29 |
1 files changed, 21 insertions, 8 deletions
@@ -2622,7 +2622,7 @@ usual printing of the variable bindings or the word false. The syntax of the @(output) directive is: - @(output [ DESTINATION ] [ :nothrow ] [ { keyword value } * ]) + @(output [ DESTINATION ] { bool-keyword | keyword value }* ) . . one or more output directives or lines . @@ -2633,21 +2633,34 @@ redirects to standard output, or a shell command preceded by the ! symbol. In the first form, the destination may be specified as a variable which holds text, a string literal or a quasiliteral -The syntax throws an exception if the output destination +The keyword list consists of a mixture of boolean keywords which +do not have an argument, or keywords with arguments. + +The following boolean keywords are supported: + +.IP :nothrow + +The output directive throws an exception if the output destination cannot be opened, unless the :nothrow keyword is present, in which -case the situation is treated as a match failure. The old syntax throws an -exception. +case the situation is treated as a match failure. Note that since command pipes are processes that report errors asynchronously, a failing command will not throw an immediate exception that can be suppressed with :nothrow. This is for synchronous errors, like trying to open a destination file, but not having permissions, etc. -The keyword value list is used for passing additional options. -Currently, the only keyword supported is the :filter keyword. -This specifies a filter to be applied to the variable substitutions occuring -within the output clause. +.IP :append + +This keyword is meaningful for files, specifying append mode: the output is to +be added to the end of the file rather than overwriting the file. + +The following value keywords are supported: + +.IP :filter +The argument is a symbol, which specifies a filter to be applied to the +variable substitutions occuring within the output clause. +See the later sections Output Filtering below, and The Deffilter Directive. .SS Output Text |