|GROFF_TRACE(7)||Standards, Environments, and Macros||GROFF_TRACE(7)|
||[option ...] [input-file ...]|
This tracing process is activated by specifying the groff or troff command-line option -m trace. This works also with the groffer(1) viewer program. A finer control can be obtained by including the macro file within the document by the groff macro call .mso trace.tmac. Only macros that are defined after this line are traced.
If the command-line option -r trace-full=1 is given (or if this register is set in the document), number and string register assignments together with some other requests are traced also.
If some other macro package should be traced as well it must be specified after -m trace on the command line.
The macro file trace.tmac is unusual because it does not contain any macros to be called by a user. Instead, the existing macro definition and appending facilities are modified such that they display diagnostic messages.
sh# echo '. > .de test_macro > .. > .test_macro > .test_macro some dummy arguments > ' | groff -m trace > /dev/null *** .de test_macro *** de trace enter: .test_macro *** trace exit: .test_macro *** de trace enter: .test_macro "some" "dummy" "arguments" *** trace exit: .test_macro "some" "dummy" "arguments"
The entry and the exit of each macro call is displayed on the terminal (standard output) — together with the arguments (if any).
sh# echo '. > .de child > .. > .de parent > .child > .. > .parent > ' | groff -m trace > /dev/null *** .de child *** .de parent *** de trace enter: .parent *** de trace enter: .child *** trace exit: .child *** trace exit: .parent
This shows that macro calls can be nested. This powerful feature can help to tack down quite complex call stacks.
sh# echo '. > .de before > .. > .mso trace.tmac > .de after > .. > .before > .after > .before > ' | groff > /dev/null *** de trace enter: .after *** trace exit: .after
Here, the tracing is activated within the document, not by a command-line option. As tracing was not active when macro before was defined, no call of this macro is protocolled; on the other hand, the macro after is fully protocolled.
normally passes ‘\\n[bar]’ to macro ‘.foo’, but with the redefined .de request it passes ‘\n[bar]’ instead.
The solution to this problem is to use groff's \E escape which is an escape character not interpreted in copy mode, for example
|29 November 2018||groff 1.22.4|