If I am fread()'ing through a file and want to append it when i find a particular item, can i just do an fwrite() when i find it or do i have to first fseek() to that location and then do an fwrite()?
candoc
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Jump to PostYou do need to do an fseek to that location, but not because C uses separate read and write pointers. The standard says that when switching between read and write mode on a stream, there needs to be a flush or seek between them. So you would read to the …
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Dave Sinkula
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Tom Gunn
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You do need to do an fseek to that location, but not because C uses separate read and write pointers. The standard says that when switching between read and write mode on a stream, there needs to be a flush or seek between them. So you would read to the location you want to write, then do fseek(strm, 0, SEEK_CUR); to switch the mode without changing the file position.
And keep in mind that you will be overwriting whatever is there, not inserting.
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