Ftell large files

In the case that the file is being written to, fflush can be used prior to calling fgetpos , ftell , or ftello to ensure the accuracy of these functions. Text mode files with no buffering do not have this problem; however, performance can be significantly degraded with buffering turned off.

Functions: fopen , fseek , lseek , popen , rewind , ungetc , write. Miscellaneous: lf On failure, they return -1 and and errno is set to one of the following values: EBADF The file descriptor underlying stream is not valid. I think it is OK to scope the rule to regular files, as I believe this is the issue we were really trying to address. I'm not sure why anyone would size a device file.

I'm guessing they aren't going to read it into memory. Or you just want to compute how much freek disk space you've got? A similar example is INTC. Ensure that unsigned integer operations do not wrap. If we were to turn this into a rule for TS , we probably wouldn't require this problem to be diagnosed unless the incorrect size value was used in a restricted sink. Pages Boards. Page tree. Browse pages. A t tachments 0 Page History People who can view. Input Output FIO. Jira links.

In addition, footnote of subclause 7. First, the fopen page says: The character ' b ' shall have no effect, but is allowed for ISO C standard conformance. Second, the fwrite page says: For each object, size calls shall be made to the fputc function, taking the values in order from an array of unsigned char exactly overlaying the object.

Noncompliant Code Example Binary File This code example attempts to open a binary file in binary mode and use fseek and ftell to obtain the file size. Igor Ignatyuk. Permalink Jul 20, David Svoboda. Yozo TODA. Just revised. Permalink Oct 22, Brian Szymanski. Permalink Jan 01, Geoff Clare.

Permalink Jan 03, Dean Sutherland. Robert Seacord. Permalink Jan 04, It certainly seems like this should be a rule and not a recommendation. Failing in cases of very large files is OK, provided it is reported as an error. I'll test the Windows program to see if it can read in an entire file I know of none. Show 1 more comment. Active Oldest Votes. Improve this answer.

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