FMEMOPEN(3) | Library Functions Manual | FMEMOPEN(3) |
FILE *
fmemopen(void *restrict buffer, size_t size, const char *restrict mode);
The mode argument has the same meaning as in fopen(3).
The stream treats the buffer as it would treat a file tracking the current position to perform I/O operations. For example, in the beginning the stream points to the beginning of the buffer, unless a was specified in the mode argument, and then it points to the first NUL byte. If a NULL buffer was specified, then the stream will always point at the first byte of the buffer.
The stream also keeps track of the size of the buffer. The size is initialized depending on the mode:
Read or write operations advance the buffer, but not to exceed the given size of the buffer. Trying to read beyond the size of the buffer results in EOF returned. NUL bytes are read normally. Trying to write beyond the size of the buffer has no effect.
When a stream open for writing is either flushed or closed, a NUL byte is written at the current position or at the end of the current size as kept internally, if there is room.
The fmemopen() function may also fail and set errno for any of the errors specified for the routine malloc(3).
October 15, 2011 | NetBSD 7.2 |