Coding Guidelines/Filesystem Manipulation

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Amanda supplies a few wrapper functions around the ordinary descriptor operations to handle a few common cases. In most cases, these functions are preferred over calling the wrapped function directly.

robust_open

in common-src/file.c

This function wraps open to retry on certain failures, and sets the close-on-exec flag.

robust_close

in common-src/file.c

This function wraps close to retry on certain failures.

full_read

in gnulib/full-read.c

This function calls read repeatedly until the given buffer is full, or an EOF or an error occurs. It handles interrupted syscalls appropriately.

full_write

in gnulib/full-read.c

Similarly, this function calls write repeatedly, until the entire buffer has been writte, or an error occurs.

portable_readdir

in common-src/util.c

This function wraps the various readdir implementations that might be available, including re-entrant and 64-bit versions, preferring 64-bit compatibility and re-entrancy.

safe_getcwd

in common-src/getcwd.c

This file provides an implementation of the getcwd procedure that uses getwd, for systems with getwd but without getcwd. It adds re-entrancy as well, by avoiding the use of static buffers.