Hi Heinrich,
On Wed, 16 Nov 2022 at 00:07, Heinrich Schuchardt heinrich.schuchardt@canonical.com wrote:
Provide a man-page for the cmp command.
Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com
doc/usage/cmd/cmp.rst | 105 ++++++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + 2 files changed, 106 insertions(+) create mode 100644 doc/usage/cmd/cmp.rst
Reviewed-by: Simon Glass sjg@chromium.org
nits below
diff --git a/doc/usage/cmd/cmp.rst b/doc/usage/cmd/cmp.rst new file mode 100644 index 0000000000..241320d328 --- /dev/null +++ b/doc/usage/cmd/cmp.rst @@ -0,0 +1,105 @@ +.. SPDX-License-Identifier: GPL-2.0+:
+cmp command +===========
+Synopsis +--------
+::
- cmp [.b, .w, .l, .q] addr1 addr2 count
+Description +-----------
+The cmp command is used to compare two memory areas. By default it works on +four byte tuples. By appending .b, .w, .l, .q the size of the tuples is +controlled:
+cmp.b
- compare 1 byte tuples
I don't think tuple is a good name for this. It is just a value.
compare single bytes
+cmp.w
- compare 2 byte tuples
2-byte (16 bit) values
+cmp.l
- compare 4 byte tuples
+cmp.q
- compare 8 byte tuples
8-byte (64-bit) values
+The parameters are used as follows:
+addr1
- Address of the first memory area.
+addr2
- Address of the second memory area.
+count
- Number of bytes to compare (as hexadecimal number).
+Example +-------
+In the example below the strings "Hello world\n" and "Hello World\n" are written +to memory and then compared.
+::
- => mm.b 0x1000000
- 01000000: 00 ? 48
- 01000001: 00 ? 65
- 01000002: 00 ? 6c
- 01000003: 00 ? 6c
- 01000004: 00 ? 6f
- 01000005: 00 ? 20
- 01000006: 00 ? 77
- 01000007: 00 ? 6f
- 01000008: 00 ? 72
- 01000009: 00 ? 6c
- 0100000a: 00 ? 64
- 0100000b: 00 ? 0d
- 0100000c: 00 ? => <INTERRUPT>
- => mm.b 0x101000
- 00101000: 00 ? 48
- 00101001: 00 ? 65
- 00101002: 00 ? 6c
- 00101003: 00 ? 6c
- 00101004: 00 ? 6f
- 00101005: 00 ? 20
- 00101006: 00 ? 57
- 00101007: 00 ? 6f
- 00101008: 00 ? 72
- 00101009: 00 ? 6c
- 0010100a: 00 ? 64
- 0010100b: 00 ? 0d
- 0010100c: 00 ? => <INTERRUPT>
- => cmp 0x1000000 0x101000 0xc
- word at 0x01000004 (0x6f77206f) != word at 0x00101004 (0x6f57206f)
- Total of 1 word(s) were the same
- => cmp.b 0x1000000 0x101000 0xc
- byte at 0x01000006 (0x77) != byte at 0x00101006 (0x57)
- Total of 6 byte(s) were the same
- => cmp.w 0x1000000 0x101000 0xc
- halfword at 0x01000006 (0x6f77) != halfword at 0x00101006 (0x6f57)
- Total of 3 halfword(s) were the same
- => cmp.l 0x1000000 0x101000 0xc
- word at 0x01000004 (0x6f77206f) != word at 0x00101004 (0x6f57206f)
- Total of 1 word(s) were the same
- => cmp.q 0x1000000 0x101000 0xc
- double word at 0x01000000 (0x6f77206f6c6c6548) != double word at 0x00101000 (0x6f57206f6c6c6548)
- Total of 0 double word(s) were the same
+Configuration +-------------
+The cmp command is only available if CONFIG_CMD_MEMORY=y. The cmp.q command is +only available if additionally CONFIG_MEM_SUPPORT_64BIT_DATA=y.
+Return value +------------
+The return value $? is true (0) if the compared memory areas are equal. +The reutrn value is false (1) if the compared memory areas differ.
return
diff --git a/doc/usage/index.rst b/doc/usage/index.rst index f7f03aeac1..b012cfc64b 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -34,6 +34,7 @@ Shell commands cmd/cat cmd/cbsysinfo cmd/cls
- cmd/cmp cmd/conitrace cmd/cyclic cmd/dm
-- 2.37.2
Regards, Simon