error - analyze and disperse compiler error messages
error [ -n ] [ -s ] [ -q ] [ -v ] [ -t suffixlist ] [ -I ignorefile ] [
Error analyzes and optionally disperses the diagnostic error messages
produced by a number of compilers and language processors to the source
file and line where the errors occurred. It can replace the painful,
traditional methods of scribbling abbreviations of errors on paper, and
permits error messages and source code to be viewed simultaneously
without machinations of multiple windows in a screen editor.
Error looks at the error messages, either from the specified file name
or from the standard input, and attempts to determine which language
processor produced each error message, determines the source file and
line number to which the error message refers, determines if the error
message is to be ignored or not, and inserts the (possibly slightly
modified) error message into the source file as a comment on the line
preceding to which the line the error message refers. Error messages
which can't be categorized by language processor or content are not
inserted into any file, but are sent to the standard output. Error
touches source files only after all input has been read. By specifying
the -q query option, the user is asked to confirm any potentially dan-
gerous (such as touching a file) or verbose action. Otherwise error
proceeds on its merry business. If the -t touch option and associated
suffix list is given, error will restrict itself to touch only those
files with suffices in the suffix list. Error also can be asked (by
specifying -v) to invoke vi(1) on the files in which error messages
were inserted; this obviates the need to remember the names of the
files with errors.
Error is intended to be run with its standard input connected via a
pipe to the error message source. Some language processors put error
messages on their standard error file; others put their messages on the
standard output. Hence, both error sources should be piped together
into error. For example, when using the csh syntax,
make -s lint |& error -q -v
will analyze all the error messages produced by whatever programs make
runs when making lint.
Error knows about the error messages produced by: make, cc, cpp, ccom,
as, ld, lint, pi, pc and f77. Error knows a standard format for error
messages produced by the language processors, so is sensitive to
changes in these formats. For all languages except Pascal, error mes-
sages are restricted to be on one line. Some error messages refer to
more than one line in more than one files; error will duplicate the
error message and insert it at all of the places referenced.
Error will do one of six things with error messages.
Some language processors produce short errors describing
which file it is processing. Error uses these to determine
the file name for languages that don't include the file name
in each error message. These synchronization messages are
consumed entirely by error.
discard Error messages from lint that refer to one of the two lint
libraries, /usr/lib/llib-lc and /usr/lib/llib-port are dis-
carded, to prevent accidently touching these libraries.
Again, these error messages are consumed entirely by error.
nullify Error messages from lint can be nullified if they refer to a
specific function, which is known to generate diagnostics
which are not interesting. Nullified error messages are not
inserted into the source file, but are written to the stan-
dard output. The names of functions to ignore are taken from
either the file named .errorrc in the users's home directory,
or from the file named by the -I option. If the file does
not exist, no error messages are nullified. If the file does
exist, there must be one function name per line.
not file specific
Error messages that can't be intuited are grouped together,
and written to the standard output before any files are
touched. They will not be inserted into any source file.
Error message that refer to a specific file, but to no spe-
cific line, are written to the standard output when that file
Error messages that can be intuited are candidates for inser-
tion into the file to which they refer.
Only true error messages are candidates for inserting into the file
they refer to. Other error messages are consumed entirely by error or
are written to the standard output. Error inserts the error messages
into the source file on the line preceding the line the language pro-
cessor found in error. Each error message is turned into a one line
comment for the language, and is internally flagged with the string
``###'' at the beginning of the error, and ``%%%'' at the end of the
error. This makes pattern searching for errors easier with an editor,
and allows the messages to be easily removed. In addition, each error
message contains the source line number for the line the message refers
to. A reasonably formatted source program can be recompiled with the
error messages still in it, without having the error messages them-
selves cause future errors. For poorly formatted source programs in
free format languages, such as C or Pascal, it is possible to insert a
comment into another comment, which can wreak havoc with a future com-
pilation. To avoid this, programs with comments and source on the same
line should be formatted so that language statements appear before com-
Options available with error are:
-n Do not touch any files; all error messages are sent to the stan-
-q The user is queried whether s/he wants to touch the file. A ``y''
or ``n'' to the question is necessary to continue. Absence of the
-q option implies that all referenced files (except those refer-
ring to discarded error messages) are to be touched.
-v After all files have been touched, overlay the visual editor vi
with it set up to edit all files touched, and positioned in the
first touched file at the first error. If vi can't be found, try
ex or ed from standard places.
-t Take the following argument as a suffix list. Files whose suf-
fixes do not appear in the suffix list are not touched. The suf-
fix list is dot separated, and ``*'' wildcards work. Thus the
allows error to touch files ending with ``.c'', ``.y'', ``.foo*''
-s Print out statistics regarding the error categorization. Not too
Error catches interrupt and terminate signals, and if in the insertion
phase, will orderly terminate what it is doing.
~/.errorrc function names to ignore for lint error messages
/dev/tty user's teletype
Opens the teletype directly to do user querying.
Source files with links make a new copy of the file with only one link
Changing a language processor's format of error messages may cause
error to not understand the error message.
Error, since it is purely mechanical, will not filter out subsequent
errors caused by `floodgating' initiated by one syntactically trivial
error. Humans are still much better at discarding these related
Pascal error messages belong after the lines affected (error puts them
before). The alignment of the `|' marking the point of error is also
disturbed by error.
Error was designed for work on CRT's at reasonably high speed. It is
less pleasant on slow speed terminals, and has never been used on hard-
4th Berkeley Distribution 18 January 1983 ERROR(1)