Awk - Revision history

Pbug: /* Awk in checksumming files */ awk doesn't like these backslashes

2008-07-05T19:20:56Z

Awk in checksumming files: awk doesn't like these backslashes

← Older revision		Revision as of 12:20, 5 July 2008
Line 75:		Line 75:
	you would use this awk command:		you would use this awk command:

	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } }
	{ file=$1; command="md5 " file; command \| getline ; if (array[$NF] == "") print $2 " has changed"; \		{ file=$1; command="md5 " file; command \| getline ; if (array[$NF] == "") print $2 " has changed";
	close (command); }'		close (command); }'

Pbug: /* Awk in checksumming files */ closing quote

2008-07-05T19:19:28Z

Awk in checksumming files: closing quote

← Older revision		Revision as of 12:19, 5 July 2008
Line 77:		Line 77:
	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \
	{ file=$1; command="md5 " file; command \| getline ; if (array[$NF] == "") print $2 " has changed"; \		{ file=$1; command="md5 " file; command \| getline ; if (array[$NF] == "") print $2 " has changed"; \
	close (command); }		close (command); }'

	It would print (if I haven't changed any files):		It would print (if I haven't changed any files):

Pbug: /* Awk in checksumming files */ should fix linuxers using gawk

2008-07-05T19:16:56Z

Awk in checksumming files: should fix linuxers using gawk

← Older revision		Revision as of 12:16, 5 July 2008
Line 76:		Line 76:

	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \
	{ file=$1; "md5 " file \| getline ; if (array[$NF] == "") print $2 " has changed"; \		{ file=$1; command="md5 " file; command \| getline ; if (array[$NF] == "") print $2 " has changed"; \
	close (~~"md5 " file~~); }		close (command); }

	It would print (if I haven't changed any files):		It would print (if I haven't changed any files):

Pbug: /* Awk in checksumming files */ wrap on several lines

2008-07-04T19:43:30Z

Awk in checksumming files: wrap on several lines

← Older revision		Revision as of 12:43, 4 July 2008
Line 75:		Line 75:
	you would use this awk command:		you would use this awk command:

	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { file=$1; "md5 " file \| getline ; if (array[$NF] == "") print $2 " has changed"; close ("md5 " file); }		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } \
			{ file=$1; "md5 " file \| getline ; if (array[$NF] == "") print $2 " has changed"; \
			close ("md5 " file); }

	It would print (if I haven't changed any files):		It would print (if I haven't changed any files):

Pbug: /* Awk in checksumming files */ this should fix runnign out of descriptors

2008-07-04T19:42:46Z

Awk in checksumming files: this should fix runnign out of descriptors

← Older revision		Revision as of 12:42, 4 July 2008
Line 75:		Line 75:
	you would use this awk command:		you would use this awk command:

	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { "md5 " $1 \| getline ; if (array[$NF] == "") print $2 " has changed" }		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { file=$1; "md5 " file \| getline ; if (array[$NF] == "") print $2 " has changed"; close ("md5 " file); }

	It would print (if I haven't changed any files):		It would print (if I haven't changed any files):

Pbug: /* Awk and multi-row documents */ better wording, row-> field

2008-07-02T15:21:58Z

Awk and multi-row documents: better wording, row-> field

← Older revision		Revision as of 08:21, 2 July 2008
Line 36:		Line 36:
	''N.B.'' This can be misleading in the case of programs that use large amounts of shared memory (like java).		''N.B.'' This can be misleading in the case of programs that use large amounts of shared memory (like java).

	== Awk and multi-~~row~~ documents ==		== Awk and multi-field documents ==

	pretend you have a file that has IP numbers where multiple can be on one row and you need to		pretend you have a file that has IP numbers where multiple can be on one row and you need to
Line 53:		Line 53:
	10.0.0.2		10.0.0.2
	10.0.0.3		10.0.0.3


	== Awk in checksumming files ==		== Awk in checksumming files ==

Pbug: /* Awk in checksumming files */

2008-07-02T13:34:59Z

Awk in checksumming files

← Older revision		Revision as of 06:34, 2 July 2008
Line 94:		Line 94:
	You can run this on your system with slight modifications, notice it takes a lot of ram because it builds an array in memory at beginning. Also in the professional world people use a script called "tripwire" to checksum and check files for signs of replacement.		You can run this on your system with slight modifications, notice it takes a lot of ram because it builds an array in memory at beginning. Also in the professional world people use a script called "tripwire" to checksum and check files for signs of replacement.

	Also note that the example is done on an OpenBSD system where md5 is the same as Linux's md5sum utility but has a slightly different output, md5 in this example is in the PATH.		Also note that the example is done on an OpenBSD system where md5 is the same as Linux's md5sum utility but has a slightly different output, [[md5]] in this example is in the PATH.

Pbug: /* Awk in checksumming files */

2008-07-02T13:34:25Z

Awk in checksumming files

← Older revision		Revision as of 06:34, 2 July 2008
Line 93:		Line 93:

	You can run this on your system with slight modifications, notice it takes a lot of ram because it builds an array in memory at beginning. Also in the professional world people use a script called "tripwire" to checksum and check files for signs of replacement.		You can run this on your system with slight modifications, notice it takes a lot of ram because it builds an array in memory at beginning. Also in the professional world people use a script called "tripwire" to checksum and check files for signs of replacement.

			Also note that the example is done on an OpenBSD system where md5 is the same as Linux's md5sum utility but has a slightly different output, md5 in this example is in the PATH.

Pbug: /* Awk in checksumming files */

2008-07-02T12:39:24Z

Awk in checksumming files

← Older revision		Revision as of 05:39, 2 July 2008
Line 78:		Line 78:
	find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { "md5 " $1 \| getline ; if (array[$NF] == "") print $2 " has changed" }		find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { "md5 " $1 \| getline ; if (array[$NF] == "") print $2 " has changed" }

	It would print (if I haven't changed any files:		It would print (if I haven't changed any files):

	== "") print $2 " has changed" }' <		== "") print $2 " has changed" }' <

Pbug at 12:37, 2 July 2008

2008-07-02T12:37:50Z

← Older revision		Revision as of 05:37, 2 July 2008
Line 53:		Line 53:
	10.0.0.2		10.0.0.2
	10.0.0.3		10.0.0.3


			== Awk in checksumming files ==

			pretend you have some files, here is a list:

			francisco$ ls
			four md5list one three two

			And you want to check these against a list called md5list (listed above too), the list is
			created like so:

			francisco$ md5 * > md5list
			francisco$ cat md5list
			MD5 (four) = 48a24b70a0b376535542b996af517398
			MD5 (md5list) = d41d8cd98f00b204e9800998ecf8427e
			MD5 (one) = b026324c6904b2a9cb4b88d6d61c81d1
			MD5 (three) = 4fbafd6948b6529caa2b78e476359875
			MD5 (two) = 26ab0db90d72e28ad0ba1e22ee510510

			And at a later time you wanted to check these checksums against your files to tell you what changed
			you would use this awk command:

			find . -type f \| awk 'BEGIN { while ( getline < "md5list") { array[$NF] = $2 } } { "md5 " $1 \| getline ; if (array[$NF] == "") print $2 " has changed" }

			It would print (if I haven't changed any files:

			== "") print $2 " has changed" }' <
			(./md5list) has changed

			Only the list itself in this case but if I were to change one:

			francisco$ echo 87 >> three
			== "") print $2 " has changed" }' <
			(./three) has changed
			(./md5list) has changed

			It tells that the "three" file has changed.

			You can run this on your system with slight modifications, notice it takes a lot of ram because it builds an array in memory at beginning. Also in the professional world people use a script called "tripwire" to checksum and check files for signs of replacement.