Applying Patches with Changed White Space.Detailed Description of diff3 Normal Format.Detailed Description of If-then-else Format.Showing Lines That Match Regular Expressions.Showing Which Sections Differences Are in.An Example of Context Format with Less Context.Binary Files and Forcing Text Comparisons.Suppressing Lines Matching a Regular Expression.Suppressing Differences in Blank and Tab Spacing.The string terminator is a byte containing all 0 bits.Comparing and Merging Files Comparing and Merging Files Short Contents The unsigned int is two or four bytes (depending on your environment) each containing all 0 bits. The two items are stored at different addresses. Your compiled code performs operations suitable for strings on the former location, and operations suitable for unsigned binary numbers on the latter. (Unless you have either a bug in your code, or some dangerously clever code!)īut all of these bytes look the same to the CPU. Data in memory (in most currently-common instruction set architectures) doesn't have any type associated with it. That's an abstraction that exists only in the source code and means something only to the compiler.Įdit-added: As an example: It is perfectly possible, even common, to perform arithmetic on the bytes that make up a string. If you have a string of 8-bit ASCII characters, you can convert the letters in the string between upper and lower case by adding or subtracting 32 (decimal). Or if you are translating to another character code you can use their values as indices into an array whose elements provide the equivalent bit coding in the other code. To the CPU the chars are really extra-short integers. (eight bits each instead of 16, 32, or 64.) To us humans their values happen to be associated with readable characters, but the CPU has no idea of that. It also doesn't know anything about the "C" convention of "null byte ends a string", either (and as many have noted in other answers and comments, there are programming environments in which that convention isn't used at all). To be sure, there are some instructions in x86/圆4 that tend to be used a lot with strings - the REP prefix, for example - but you can just as well use them on an array of integers, if they achieve the desired result. The scientific single word answer would be: metadata. This metadata can be part of the program Code (as The metadata tells the computer whether some data at a certain location is an int, a string, program code or whatever. Jamie Hanrahan mentioned) or it can be explicitly stored somewhere. Modern CPUs can often distinguish between memory regions assigned to program code and data regions (for example, the NX Bit ). Some exotic hardware can also distinguish between strings and numbers, yes. But the usual case is that the Software takes care of this issue, either though implicit metadata (in the code) or explicit metadata (object-oriented VMs often store the metadata (type/class information) as part of the data (object)).Īn advantage of not distinguishing between different kinds of data is that some operations become very simple. The I/O subsystem does not necessarily need to know whether the data it just reads from or writes to disk is actually program code, human readable text or numbers. It's all just bits which get transported through the machine. Let the program code deal with the fancy typing issues.I am trying to compare Stored procedures between two databases. I have the following scripts written and another from google. The query works fine, But it is also taking the blank spaces into account and showing that the queries are not matching. I do not know how to eliminate the blank space in comparsion of queries. Can someone modify these queries or give me some queries or suggestions of how to compare stored procedures only text.
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