Content-type: text/html Man page of error

error

Section: User Commands (1)
Index Return to Main Contents
 

NAME

error - Analyzes and disperses compiler error messages  

SYNOPSIS

error [-n] [-q] [-s] [-v] [-t suffix_list] [-I ignore_file] [file]

The error program 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.
 

OPTIONS

Takes the names of functions to ignore from ignore_file. If the -I option is not specified, the function names are taken from a file named .errorrc in the user's home directory. If this file does not exist, no error messages are nullified. Function names must be listed one per line in ignore_file or in the .errorrc file. Does not touch any files; all error messages are sent to the standard output. Queries the user whether or not to touch the file. You must enter y or n, or the locale's equivalent of an affirmative or negative response, before continuing. If you do not specify the -q option, all referenced files (except those referring to discarded error messages) are touched by default. Prints out statistics regarding the error categorization. Does not touch files whose suffixes do not appear suffix_list. The suffix list is dot-separated, and * wildcards may be used. For example, the suffix list .c.y.foo*.h allows error to touch files ending with .c, .y, .foo* and .y. Overlays and sets up the visual editor vi to edit all files touched, and positions the editor at the first error in the first touched file. If vi cannot be found, try ex or ed from standard places.
 

DESCRIPTION

Using the error program 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.

The error program looks at the error messages, either from the specified file file or from the standard input, and performs the following operations: 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. 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. Sends error messages that cannot be categorized by language processor or content to the standard output; does not insert these error messages into any file.

The error program touches source files only after all input has been read.

The error program 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, the following command line analyzes all the error messages produced by whatever programs make runs when making lint: make -s lint | error -q -v

The error program knows about the error messages produced by the following programs: as cc ccom cpp f77 ld lint make pc pi

The error program 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 messages are restricted to be on one line. Some error messages refer to more than one line in more than one file; error duplicates the error message and inserts it at all of the places referenced.

The error program does one of six things with error messages: Some language processors produce short errors describing which file it is processing. The error program uses these to determine the file name for languages that do not include the file name in each error message. These synchronization messages are consumed entirely by error. Error messages from lint that refer to one of the two lint libraries, /usr/libdata/lint/llib-lc and /usr/libdata/lint/llib-port are discarded, to prevent accidentally touching these libraries. Again, these error messages are consumed entirely by error. 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 lint functions to ignore are taken from either the file named .errorrc in the user'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. Error messages that cannot be ``intuited'' are grouped together, and written to the standard output before any files are touched. These messages are not inserted into any source file. Error message that refer to a specific file, but to no specific line, are written to the standard output when that file is touched. 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 to which they refer. Other error messages are consumed entirely by error or are written to the standard output. The error program 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 to which the message refers. 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.

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

NOTES

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. The error program, since it is purely mechanical, does 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 error. error was designed for work on CRTs at reasonably high speed. It is less pleasant on slow speed terminals, and has never been used on hardcopy terminals.
 

FILES

Function names to ignore for lint error messages. User's teletype.


 

Index

NAME
SYNOPSIS
OPTIONS
DESCRIPTION
NOTES
FILES

This document was created by man2html, using the manual pages.
Time: 02:42:48 GMT, October 02, 2010