Geoff Chappell - Software Analyst
This option names a file to receive the dump.
The required filename argument consists of everything after the colon. It is a fatal error (LNK1104) if filename cannot be opened (in text mode) with exclusive write access. If the named file does not exist already, it is created. If it does exist already, it is truncated.
Though the general idea is that all DUMPBIN output goes to the filename from the last /out option, there are some exceptions. Knowledge of them may help decide whether to use /out or to redirect standard output. First, the so-called logo, including its echo of options picked up from command files, necessarily goes to standard output. So also do errors and warnings. The announcement of each input file, beginning “Dump of file”, goes to standard error if the /map option is given.
Each instance of /out must satisfy the requirements described above for the syntax, including the creation or truncation of filename. Otherwise, each overrides the filename set by any preceding /out.
A curiosity—really of no practical consequence—is that when DUMPBIN opens a file named in one /out, it doesn’t close the file from any previous /out. This suggests that use of multiple /out options was just not anticipated, neither as something to support nor as something to defend against. The C Run-Time provides for 512 streams to be open simultaneously. Allowing for 3 standard handles gives the prediction that 510 /out options (in a command file), each naming a different file, will be one too many, so that the last produces the fatal error LNK1104.