Program:      xfile

Purpose:      General file extractor.

Category:     SYSTEM MANAGEMENT

File:         xfile.c

Author:       J.P. Terlouw


Use:          xfile <fn> [-d<sym>] [-u<sym>] [-p<path>]  [-n<name>] [-w<wc>]
              <fn>        input file from which to extract files
              <path>      path to where extracted files will be written
              <sym>       symbol to be (un)defined
              <name>      only file names matching name will be extracted.
                          Wildcards are allowed. Default all files will
                          be extracted.
              <wc>        set the wildcard in <name>. Default is *.

Description:  Xfile extracts files from its input file. Files to be
              extracted are indicated by:  #>name  or %#>name at the
              beginning of an input line. The % in the second form can be
              any character. This character is then used as a flag
              character which must be the first character in subsequent
              lines belonging to this file. It is not copied to the
              output file, i.e. it is stripped off. Lines without the
              flag character are simply discarded. The end of a file to be
              extracted is indicated by #< or %#< .
              The input file can contain any number of files to be
              extracted which can also be nested. The names of the
              extracted files are written to standard output and are
              exactly (!) the same as stated in the input file.
              Conditional file extraction is also possible. A line
              containing a conditional statement is indicated by:
              #!<statement> or %#!<statement> at the beginning of an input
              line. The % in the second form can be any character. This
              character is NOT a flag character! The conditional statements
              allowed are: IF   <symbol> [<symbol> [...] ]
                           ELIF <symbol> [<symbol> [...] ]
                           ELSE
                           ENDIF

              A symbol can be any name (not containing white space) which
              can be defined by the system (ALLIANT, CONVEX, SUN etc.) or
              by the user on the command line.

Example:      File to be processed by xfile:

              0a
              #>    xfile.ou1
              1a
              *#>   xfile.ou2
              *2a
              *2b
              2b'
              *2c
              #<
              1b
              1c
              #<
              ##>   xfile.ou3
              #1A
              #1B
              #1C
              1C'
              #1D
              ##<
              0b
              0c

              Resulting files:

              (xfile.ou1:)
              1a
              1b
              1c

              (xfile.ou2:)
              2a
              2b
              2c

              (xfile.ou3:)
              1A
              1B
              1C
              1D

Updates:      Sep 23, 1989: JPT, original document.
              Oct 11, 1989: KGB, option -d and -t implemented.
              Apr 13, 1991: KGB, conditional file extraction implemented.
              Sep 16, 1991: KGB, unrecognized directives are skipped.
              Jan 14, 1993: KGB, Bug in -n switch repaired.
              Jan 14, 1998: JPT, Bug in checkLine repaired.
              Jun 20, 2007: JPT, Drastic increase in maximum line length.
              Feb 26, 2010: JPT, Maximum line length increased to 262143.