1*61945Sbostic# @(#)README 8.1 (Berkeley) 06/06/93 242269Sbostic 342269Sbosticcol - filter out reverse line feeds. 442269Sbostic 542269SbosticOptions are: 642269Sbostic -b do not print any backspaces (last character written is printed) 742269Sbostic -f allow half line feeds in output, by default characters between 842269Sbostic lines are pushed to the line below 942269Sbostic -x do not compress spaces into tabs. 1042269Sbostic -l num keep (at least) num lines in memory, 128 are kept by default 1142269Sbostic 1242269SbosticIn the 32V source code to col(1) the default behavior was to NOT compress 1342269Sbosticspaces into tabs. There was a -h option which caused it to compress spaces 1442269Sbosticinto tabs. There was no -x flag. 1542269Sbostic 1642269SbosticThe 32V documentation, however, was consistent with the SVID (actually, V7 1742269Sbosticat the time) and documented a -x flag (as defined above) while making no 1842269Sbosticmention of a -h flag. Just before 4.3BSD went out, CSRG updated the manual 1942269Sbosticpage to reflect the way the code worked. Suspecting that this was probably 2042269Sbosticthe wrong way to go, this version adopts the SVID defaults, and no longer 2142269Sbosticdocuments the -h option. 2242269Sbostic 2342269SbosticThe S5 -p flag is not supported because it isn't clear what it does (looks 2442269Sbosticlike a kludge introduced for a particular printer). 2542269Sbostic 2642269SbosticKnown differences between AT&T's col and this one (# is delimiter): 2742269Sbostic Input AT&T col this col 2842269Sbostic #\nabc\E7def\n# # def\nabc\r# # def\nabc\n# 2942269Sbostic #a# ## #a\n# 3042269Sbostic - last line always ends with at least one \n (or \E9) 3142269Sbostic #1234567 8\n# #1234567\t8\n# #1234567 8\n# 3242269Sbostic - single space not expanded to tab 3342269Sbostic -f #a\E8b\n# #ab\n# # b\E9\ra\n# 3442269Sbostic - can back up past first line (as far as you want) so you 3542269Sbostic *can* have a super script on the first line 3642269Sbostic #\E9_\ba\E8\nb\n# #\n_\bb\ba\n# #\n_\ba\bb\n# 3742269Sbostic - always print last character written to a position, 3842269Sbostic AT&T col claims to do this but doesn't. 3942269Sbostic 4042269SbosticIf a character is to be placed on a line that has been flushed, a warning 4142269Sbosticis produced (the AT&T col is silent). The -l flag (not in AT&T col) can 4242269Sbosticbe used to increase the number of lines buffered to avoid the problem. 4342269Sbostic 4442269SbosticGeneral algorithm: a limited number of lines are buffered in a linked 4542269Sbosticlist. When a printable character is read, it is put in the buffer of 4642269Sbosticthe current line along with the column it's supposed to be in. When 4742269Sbostica line is flushed, the characters in the line are sorted according to 4842269Sbosticcolumn and then printed. 49