system---execute command string
#include <stdlib.h> int system(char *s); int _system_r(void *reent, char *s);
system to pass a command string
your system, and wait for it to finish executing.
system(NULL)' to test whether your system has
The alternate function
_system_r is a reentrant version. The
extra argument reent is a pointer to a reentrancy structure.
system(NULL) returns a non-zero value if
/bin/sh is available, and
0 if it is not.
With a command argument, the result of
system is the exit status
ANSI C requires
system, but leaves the nature and effects of a
command processor undefined. ANSI C does, however, specify that
system(NULL) return zero or nonzero to report on the existence of
a command processor.
system, and requires that it invoke a
sh is found is left unspecified.
Supporting OS subroutines required:
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