03-11-2013
Well, tail -f can be a problem to manage, but the file is the file. Data can get hung up in the pipe, too. Shell can find strings without calling grep, using case. Logs can be written in blocks from a FILE* buffer. You could poll and just tail a big hunk of file. You could figure how many lines you have checked and just check up-file of there. Really economical and efficient solutions would be in C, where you can mmap() the file as it growns and monitor the content with low overhead just in areas not already checked.
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3
4
5
6
7
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CSREQ(1) BSD General Commands Manual CSREQ(1)
NAME
csreq -- Expert tool for manipulating Code Signing Requirement data
SYNOPSIS
csreq [-v] -r requirement-input -t
csreq [-v] -r requirement-input -b outputfile
DESCRIPTION
The csreq command manipulates Code Signing Requirement data. It reads one requirement from a file or command arguments, converts it into
internal form, checks it, and then optionally outputs it in a different form.
The options are as follows:
-b path
Requests that the requirement read be written in binary form to the path given.
-r requirement-input
Specifies the input requirement. See "specifying requirements" below. This is exactly the same format as is accepted by the -r and -R
options of the codesign(1) command.
-t Requests that the requirement read be written as text to standard output.
-v Increases the verbosity of output. Multiple instances of -v produce increasing levels of commentary output.
In the first synopsis form, csreq reads a Code Requirement and writes it to standard output as canonical source text. Note that with text
input, this actually compiles the requirement into internal form and then converts it back to text, giving you the system's view of the
requirement code.
In the second synopsis form, csreq reads a Code Requirement and writes its binary representation to a file. This is the same form produced by
the SecRequirementCopyData API, and is readily acceptable as input to Code Signing verification APIs. It can also be used as input to subse-
quent invocations of csreq by passing the filename to the -r option.
SPECIFYING REQUIREMENTS
The requirement argument (-r) can be given in various forms. A plain text argument is taken to be a path to a file containing the require-
ment. This program will accept both binary files containing properly compiled requirements code, and source files that are automatically com-
piled for use. An argument of "-" requests that the requirement(s) are read from standard input. Again, standard input can contain either
binary form or text. Finally, an argument that begins with an equal sign "=" is taken as a literal requirements source text, and is compiled
accordingly for use.
EXAMPLES
To compile an explicit requirement program and write its binary form to file "output":
csreq -r="identifier com.foo.test" -b output.csreq
To display the requirement program embedded at offset 1234 of file "foo":
tail -b 1234 foo | csreq -r- -t
FILES
DIAGNOSTICS
The csreq program exits 0 on success or 1 on failure. Errors in arguments yield exit code 2.
SEE ALSO
codesign(1)
HISTORY
The csreq command first appeared in Mac OS 10.5.0 .
BSD
June 1, 2006 BSD