


      ERROR(1)                    (bsd 4.2)                    ERROR(1)



      NAME
           error - analyze and disperse compiler error messages

      SYNTAX
           error [ -n ] [ -s ] [ -q ] [ -v ] [ -t suffixlist ] [ -I
           ignorefile ] [ name ]

      DESCRIPTION
           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 dangerous (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, and f77. Error knows a standard



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           format for error messages produced by the language
           processors, so is sensitive to changes in these formats.
           For all languages, error messages are restricted to be on
           one line.  Some error messages refer to more than one line
           in more than one file; 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.

           synchronize
                     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 discarded, 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 standard
                     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.

           file specific
                     Error message that refer to a specific file, but
                     to no specific line, are written to the standard
                     output when that file is touched.

           true errors
                     Error messages that can be intuited are candidates
                     for insertion 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



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           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 processor 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 themselves 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 compilation.
           To avoid this, programs with comments and source on the same
           line should be formatted so that language statements appear
           before comments.

           Options available with error are:

           -n   Do not touch any files; all error messages are sent to
                the standard output.

           -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 referring 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 suffixes do not appear in the suffix list are not
                touched.  The suffix list is dot separated, and ``*''
                wildcards work.  Thus the suffix list:

                     ".c.y.foo*.h"

                allows error to touch files ending with ``.c'', ``.y'',
                ``.foo*'' and ``.h''.

           -s   Print out statistics regarding the error
                categorization.  Not too useful.

           Error catches interrupt and terminate signals, and if in the
           insertion phase, will orderly terminate what it is doing.



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      FILES
           ~/.errorrc          function names to ignore for lint error
           messages
           /dev/tty            user's teletype

      BUGS
           Opens the teletype directly to do user querying.

           Source files with links make a new copy of the file with
           only one link to it.

           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 errors.

           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 hardcopy terminals.

































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