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/* system( const char * )
This file is part of the Public Domain C Library (PDCLib).
Permission is granted to use, modify, and / or redistribute at will.
*/
#include <stdlib.h>
/* This is an example implementation of system() fit for use with POSIX kernels.
*/
extern int fork( void );
extern int execve( const char * filename, char * const argv[], char * const envp[] );
extern int wait( int * status );
int system( const char * string )
{
const char * argv[] = { "sh", "-c", NULL, NULL };
argv[2] = string;
if ( string != NULL )
{
int pid = fork();
if ( pid == 0 )
{
execve( "/bin/sh", (char * * const)argv, NULL );
}
else if ( pid > 0 )
{
while( wait( NULL ) != pid );
}
}
return -1;
}
#ifdef TEST
#include "_PDCLIB_test.h"
#define SHELLCOMMAND "echo 'SUCCESS testing system()'"
int main( void )
{
FILE * fh;
char buffer[25];
buffer[24] = 'x';
TESTCASE( ( fh = freopen( testfile, "wb+", stdout ) ) != NULL );
TESTCASE( system( SHELLCOMMAND ) );
rewind( fh );
TESTCASE( fread( buffer, 1, 24, fh ) == 24 );
TESTCASE( memcmp( buffer, "SUCCESS testing system()", 24 ) == 0 );
TESTCASE( buffer[24] == 'x' );
TESTCASE( fclose( fh ) == 0 );
TESTCASE( remove( testfile ) == 0 );
return TEST_RESULTS;
}
#endif
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