Return to README CVS log

Up to [local] / src / usr.bin / col

Annotation of src/usr.bin/col/README, Revision 1.1

1.1     ! deraadt     1: #      @(#)README      8.1 (Berkeley) 6/6/93
        !             2:
        !             3: col - filter out reverse line feeds.
        !             4:
        !             5: Options are:
        !             6:        -b      do not print any backspaces (last character written is printed)
        !             7:        -f      allow half line feeds in output, by default characters between
        !             8:                lines are pushed to the line below
        !             9:        -x      do not compress spaces into tabs.
        !            10:        -l num  keep (at least) num lines in memory, 128 are kept by default
        !            11:
        !            12: In the 32V source code to col(1) the default behavior was to NOT compress
        !            13: spaces into tabs.  There was a -h option which caused it to compress spaces
        !            14: into tabs.  There was no -x flag.
        !            15:
        !            16: The 32V documentation, however, was consistent with the SVID (actually, V7
        !            17: at the time) and documented a -x flag (as defined above) while making no
        !            18: mention of a -h flag.  Just before 4.3BSD went out, CSRG updated the manual
        !            19: page to reflect the way the code worked.  Suspecting that this was probably
        !            20: the wrong way to go, this version adopts the SVID defaults, and no longer
        !            21: documents the -h option.
        !            22:
        !            23: The S5 -p flag is not supported because it isn't clear what it does (looks
        !            24: like a kludge introduced for a particular printer).
        !            25:
        !            26: Known differences between AT&T's col and this one (# is delimiter):
        !            27:        Input                   AT&T col                this col
        !            28:        #\nabc\E7def\n#         #   def\nabc\r#         #   def\nabc\n#
        !            29:        #a#                     ##                      #a\n#
        !            30:                - last line always ends with at least one \n (or \E9)
        !            31:        #1234567 8\n#           #1234567\t8\n#          #1234567 8\n#
        !            32:                - single space not expanded to tab
        !            33:      -f #a\E8b\n#              #ab\n#                  # b\E9\ra\n#
        !            34:                - can back up past first line (as far as you want) so you
        !            35:                  *can* have a super script on the first line
        !            36:        #\E9_\ba\E8\nb\n#       #\n_\bb\ba\n#           #\n_\ba\bb\n#
        !            37:                - always print last character written to a position,
        !            38:                  AT&T col claims to do this but doesn't.
        !            39:
        !            40: If a character is to be placed on a line that has been flushed, a warning
        !            41: is produced (the AT&T col is silent).   The -l flag (not in AT&T col) can
        !            42: be used to increase the number of lines buffered to avoid the problem.
        !            43:
        !            44: General algorithm: a limited number of lines are buffered in a linked
        !            45: list.  When a printable character is read, it is put in the buffer of
        !            46: the current line along with the column it's supposed to be in.  When
        !            47: a line is flushed, the characters in the line are sorted according to
        !            48: column and then printed.