Return Code 127
Exit codes and kill-job signals
The exit code from a batch job is a standard Unix termination status, the same sort of number you get in a shell script from checking the "$?" variable after executing a command.
Typically, exit code 0 (zero) means successful completion. Codes 1-127 are typically generated by your job itself calling exit() with a non-zero value to terminate itself and indicate an error. In BaBar we don't make very much use of this. The most common such value you might see is 64, which is the value used by Framework to say that its event loop is being stopped before all the requested data have been read, typically because time ran out. In recent BaBar releases you might also see 125, which we use as a code for a generic "severe error"; the job log should contain a message stating what the error was.
Exit codes in the range 129-255 represent jobs terminated by Unix "signals". Each type of signal has a number, and what's reported as the job exit code is the signal number plus 128. Signals can arise from within the process itself (as for SEGV, see below) or be sent to the process by some external agent (such as the batch control system, or your using the "bkill" command).
By way of example, then, exit code 64 means that the job deliberately terminated its execution by calling "exit(64)", exit code 137 means that the job received a signal 9, and exit code 140 represents signal 12.
The specific meaning of the signal numbers is platform-dependent. If you are trying to figure out a problem that was seen on Linux, you have to run the following commands on Linux. We don't have Solaris or Mac OS batch resources in BaBar at the moment, but if we did, you would have to match platforms similarly when debugging.
If a command is not found, the child process created to execute it returns a status of 127. If a com-
mand is found but is not executable, the return status is 126.
If a command fails because of an error during expansion or redirection, the exit status is greater than
zero.
Shell builtin commands return a status of 0 (true) if successful, and non-zero (false) if an error
occurs while they execute. All builtins return an exit status of 2 to indicate incorrect usage.
Bash itself returns the exit status of the last command executed, unless a syntax error occurs, in
which case it exits with a non-zero value. See also the exit builtin command below.refer to : http://stackoverflow.com/questions/1763156/127-return-code-from
thank http://stackoverflow.com/users/212762/apbianco
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