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author | Denys Vlasenko <vda.linux@googlemail.com> | 2021-02-26 17:11:55 +0100 |
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committer | Denys Vlasenko <vda.linux@googlemail.com> | 2021-02-26 17:11:55 +0100 |
commit | 9037757c5fde77d74e24e100efd70420a51c5d95 (patch) | |
tree | 8e9f88df6e4f2beb8865f06d4deadb7d47d0f763 | |
parent | 1a37aa7a88722f49928f6cd7851476aa4525462d (diff) | |
download | busybox-9037757c5fde77d74e24e100efd70420a51c5d95.tar.gz |
dc: more docs in --help
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r-- | miscutils/bc.c | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/miscutils/bc.c b/miscutils/bc.c index cc48ed3fe..934a1f8ba 100644 --- a/miscutils/bc.c +++ b/miscutils/bc.c @@ -143,12 +143,13 @@ //usage: "\n~ - divide with remainder" //usage: "\n| - modular exponentiation" //usage: "\nv - square root" -//////// "\n_NNN - push neagtive number -NNN -//////// "\n[string] - push string +//////// "\nA-F - digits 10..15 +//////// "\n_NNN - push negative number -NNN +//////// "\n[string] - push string (in FreeBSD, \[, \] and \\ are escapes, not implemented here and in GNU) //////// "\nR - DC_LEX_POP pop and discard //////// "\nc - DC_LEX_CLEAR_STACK clear stack -//////// "\nd - DC_LEX_DUPLICATE pop, push, push -//////// "\nr - DC_LEX_SWAP pop 1, pop 2, push 1, push 2 +//////// "\nd - DC_LEX_DUPLICATE duplicate top-of-stack +//////// "\nr - DC_LEX_SWAP swap top-of-stack //////// "\n:r - DC_LEX_COLON pop index, pop value, store to array 'r' //////// "\n;r - DC_LEX_SCOLON pop index, fetch from array 'r', push //////// "\nLr - DC_LEX_LOAD_PO, pop register 'r', push @@ -157,21 +158,21 @@ //////// "\nsr - DC_LEX_OP_ASSIGN pop, assign to register 'r' //////// "\n? - DC_LEX_READ read line and execute //////// "\nx - DC_LEX_EXECUTE pop string and execute -//////// "\n<r - XC_LEX_OP_REL_GT pop, pop, execute register 'r' if top-of-stack was greater -//////// "\n>r - XC_LEX_OP_REL_LT pop, pop, execute register 'r' if top-of-stack was less +//////// "\n<r - XC_LEX_OP_REL_GT pop, pop, execute register 'r' if top-of-stack was less +//////// "\n>r - XC_LEX_OP_REL_LT pop, pop, execute register 'r' if top-of-stack was greater //////// "\n=r - XC_LEX_OP_REL_EQ pop, pop, execute register 'r' if equal -//////// "\n!<r !>r !=r - negated forms -//////// "\ne - DC_LEX_ELSE >tef: "if greater execute 't' else execute 'f'" +//////// "\n !<r !>r !=r - negated forms +//////// "\n >tef - "if greater execute register 't' else execute 'f'" //////// "\nQ - DC_LEX_NQUIT pop, "break N" from macro invocations //////// "\nq - DC_LEX_QUIT "break 2" (if less than 2 levels of macros, exit dc) //////// "\nX - DC_LEX_SCALE_FACTOR pop, push number of fractional digits //////// "\nZ - DC_LEX_LENGTH pop, push number of digits it has (or number of characters in string) //////// "\na - DC_LEX_ASCIIFY pop, push low-order byte as char or 1st char of string -//////// "\n( - DC_LEX_LPAREN (not in GNU) pop, pop, if top-of-stack was less push 1 else push 0 -//////// "\n{ - DC_LEX_LBRACE (not in GNU) pop, pop, if top-of-stack was less-or-equal push 1 else push 0 -//////// "\nG - DC_LEX_EQ_NO_REG (not in GNU) pop, pop, if equal push 1 else push 0 -//////// "\nN - DC_LEX_OP_BOOL_NOT (not in GNU) pop, if 0 push 1 else push 0 -//////// "\n_ - XC_LEX_NEG (not a command - starts negative number) +//////// "\n( - DC_LEX_LPAREN (FreeBSD, not in GNU) pop, pop, if top-of-stack was less push 1 else push 0 +//////// "\n{ - DC_LEX_LBRACE (FreeBSD, not in GNU) pop, pop, if top-of-stack was less-or-equal push 1 else push 0 +//////// "\nG - DC_LEX_EQ_NO_REG (FreeBSD, not in GNU) pop, pop, if equal push 1 else push 0 +//////// "\nN - DC_LEX_OP_BOOL_NOT (FreeBSD, not in GNU) pop, if 0 push 1 else push 0 +//////// FreeBSD also has J and M commands, used internally by bc //////// "\nn - DC_LEX_PRINT_POP pop, print without newline //////// "\nP - DC_LEX_PRINT_STREAM pop, print string or hex bytes //usage: ) |