Scan

Scan Files

All files to be scanned for pattern matches should be named after the pattern or pattern input file on the command line.

Any file name prefixed with '@' will be treated as a list file. Each line is treated as if it was inserted in the original command line where the list file was named. Options may be toggled and new scan files or list files named. Leading and trailing blanks and tabs are ignored. All lines for which the first non-blank character == '#' are treated as comment lines and ignored.

A superset of the DOS wildcards are recognized and may be in either the path or filename portion of a file identification specification for file specifications on either the QTGrep command line or in list file lines. The following modified regular expression operators are recognized in paths and filename.ext: (The equivalent Regular Expression is shown in parenthesis)

 * == match any character zero or more times    (== .*),
 ? == match any character zero or one time      (== .?),
 + == match any character one or more times     (== .+),
 | == or symbol between equivalent expressions
 () parenthesis for bracketing
 [] brackets for equivalent position characters
 '!' or '^' as 1st character negates
 '-' indicates character range
 r@s r expression matched only when followed by s expression.

The last full name ending the pattern will be interpreted as a filename(.ext). If the pattern ends with an OS path separator character, the filename pattern, '*' for OS/2 and U**x style OSs, will be used automatically. Preceeding a file specification with '!' will select only those files NOT MATCHING the pattern.

QTGrep treats lines with the following form specially in list files:

dependent_file: target_file_1 target_file_2 ...

The date/time stamp for the dependent file, "dependent_file" is compared with the date/time stamps for each of the target files listed, "target_file_1", "target_file_2", etc. If the date/time stamp for any of the target files is newer than that of the dependent file, all target files are scanned for matches. Any target file name may incorporate wild card characters as described above. In addition, if the 's' option is active, subdirectories will be searched for filename matches. Normally QTGrep writes all output to the standard output file. In this case, all output is written to the dependent file. Any information currently in the dependent file is lost. If the date/time stamp for the dependent file is newer than the date/time stamp of all target files, no action is taken.

A list file of the form:

    dep_file_1: target_file_1
    dep_file_2: target_file_2
    dep_file_3: target_file_3
    .
    .
    .

will scan only the target files with date/time stamps newer than the corresponding dependent file, updating the dependent file.