4BSD/usr/man/cat1/error.1
ERROR(1) UNIX Programmer's Manual ERROR(1)
NAME
error - analyze and disperse compiler error messages
SYNOPSIS
error [ -n ] [ -s ] [ -q ] [ -v ] [ -t suffixlist ] [ -I
ignorefile ] [ name ]
DESCRIPTION
_E_r_r_o_r analyzes and optionally disperses the diagnostic error
messages produced by a number of compilers and language pro-
cessors 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.
_E_r_r_o_r looks at the error messages, either from the specified
file _n_a_m_e or from the standard input, and attempts to deter-
mine 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 modi-
fied) error message into the source file as a comment on the
line preceeding to which the line the error message refers.
Error messages which can't be categorized by language pro-
cessor or content are not inserted into any file, but are
sent to the standard output. _E_r_r_o_r 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. Oth-
erwise _e_r_r_o_r proceeds on its merry business. If the -t
touch option and associated suffix list is given, _e_r_r_o_r will
restrict itself to touch only those files with suffices in
the suffix list. Error also can be asked (by specifying -v)
to invoke _v_i(1) on the files in which error messages were
inserted; this obviates the need to remember the names of
the files with errors.
_E_r_r_o_r is intended to be run with its standard input con-
nected 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 out-
put. Hence, both error sources should be piped together
into _e_r_r_o_r. For example, when using the _c_s_h syntax,
make -s lint |& error -q -v
will analyze all the error messages produced by whatever
programs _m_a_k_e runs when making lint.
_E_r_r_o_r knows about the error messages produced by: _m_a_k_e, _c_c,
_c_p_p, _c_c_o_m, _a_s, _l_d, _l_i_n_t, _p_i, _p_c and _f_7_7. _E_r_r_o_r knows a
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ERROR(1) UNIX Programmer's Manual ERROR(1)
standard format for error messages produced by the language
processors, so is sensitive to changes in these formats.
For all languages except _P_a_s_c_a_l, error messages are res-
tricted to be on one line. Some error messages refer to
more than one line in more than one files; _e_r_r_o_r will dupli-
cate the error message and insert it at all of the places
referenced.
_E_r_r_o_r will do one of six things with error messages.
_s_y_n_c_h_r_o_n_i_z_e
Some language processors produce short errors
describing which file it is processing. _E_r_r_o_r
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 _e_r_r_o_r.
_d_i_s_c_a_r_d Error messages from _l_i_n_t that refer to one of the
two _l_i_n_t libraries, /_u_s_r/_l_i_b/_l_l_i_b-_l_c and
/_u_s_r/_l_i_b/_l_l_i_b-_p_o_r_t are discarded, to prevent
accidently touching these libraries. Again, these
error messages are consumed entirely by _e_r_r_o_r.
_n_u_l_l_i_f_y Error messages from _l_i_n_t 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 out-
put. The names of functions to ignore are taken
from either the file named ._e_r_r_o_r_r_c in the users's
home directory, or from the file named by the -I
option. If the file does not exist, no error mes-
sages are nullified. If the file does exist,
there must be one function name per line.
_n_o_t _f_i_l_e _s_p_e_c_i_f_i_c
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.
_f_i_l_e _s_p_e_c_i_f_i_c
Error message that refer to a specific file, but
to no specific line, are written to the standard
output when that file is touched.
_t_r_u_e _e_r_r_o_r_s
Error messages that can be intuited are candidates
for insertion into the file to which they refer.
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ERROR(1) UNIX Programmer's Manual ERROR(1)
Only true error messages are candidates for inserting into
the file they refer to. Other error messages are consumed
entirely by _e_r_r_o_r or are written to the standard output.
_E_r_r_o_r inserts the error messages into the source file on the
line preceeding 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 format-
ted source programs in free format languages, such as C or
Pascal, it is possible to insert a comment into another com-
ment, which can wreak havoc with a future compilation. To
avoid this, format the source program so there are no
language statements on the same line as the end of a com-
ment.
Options available with _e_r_r_o_r are:
-n Do _n_o_t touch any files; all error messages are sent to
the standard output.
-q The user is _q_u_e_r_i_e_d 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 refering to discarded
error messages) are to be touched.
-v After all files have been touched, overlay the visual
editor _v_i with it set up to edit all files touched, and
positioned in the first touched file at the first
error. If _v_i can't be found, try _e_x or _e_d from stan-
dard places.
-t Take the following argument as a suffix list. Files
whose suffices do not appear in the suffix list are not
touched. The suffix list is dot seperated, and ``*''
wildcards work. Thus the suffix list:
".c.y.foo*.h"
allows _e_r_r_o_r to touch files ending with ``.c'', ``.y'',
``.foo*'' and ``.y''.
-s Print out _s_t_a_t_i_s_t_i_c_s regarding the error categoriza-
tion. Not too useful.
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ERROR(1) UNIX Programmer's Manual ERROR(1)
_E_r_r_o_r catches interrupt and terminate signals, and if in the
insertion phase, will orderly terminate what it is doing.
AUTHOR
Robert Henry
FILES
~/.errorrc function names to ignore for _l_i_n_t 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 _e_r_r_o_r to not understand the error message.
_E_r_r_o_r, 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.
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 _e_r_r_o_r.
_E_r_r_o_r 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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