Red Hat ENTERPRISE LINUX 3 - SECURITY GUIDE, Manual

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Appendix D. gdb Remote Serial Protocol 347
D.7.10.11. system
Synopsis: int system(const char *command);
Request:
Fsystem,commandptr/len
Return value:
The value returned is -1 on error and the return status
of the command otherwise. Only the exit status of the
command is returned, which is extracted from the hosts
system return value by calling WEXITSTATUS(retval).
In case /bin/sh could not be executed, 127 is returned.
Errors:
EINTR
The call was interrupted by the user.
D.7.11. Protocol specific representation of datatypes
D.7.11.1. Integral datatypes
The integral datatypes used in the system calls are
int, unsigned int, long, unsigned long, mode_t and time_t
Int
,
unsigned int
,
mode_t
and
time_t
are implemented as 32 bit values in this protocol.
Long
and
unsigned long
are implemented as 64 bit types.
Refer to Section D.7.12.5 Limits , for corresponding MIN and MAX values (similar to those in
limits.h
) to allow range checking on host and target.
time_t
datatypes are defined as seconds since the Epoch.
All integral datatypes transferred as part of a memory read or write of a structured datatype e.g. a
struct stat
have to be given in big endian byte order.
D.7.11.2. Pointer values
Pointers to target data are transmitted as they are. An exception is made for pointers to buffers for
which the length isn’t transmitted as part of the function call, namely strings. Strings are transmitted
as a pointer/length pair, both as hex values, e.g.
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