IBM Version 4 manual Appendix B. Original Examples in Additional BLanguages-177

int main ()

{

.1/

/\ Get and print the real user id with the getuid() function. \/￿ UserID = getuid();

printf("The real user id is %u. \n",UserID);

.2/

/\ Get the current working directory and store it in Initia￿lDirectory. \/ if ( NULL == getcwd(InitialDirectory,BUFFER_SIZE) )

{

perror("getcwd Error"); CleanUpOnError(1); return ð;

}

printf("The current working directory is %s. \n",InitialDi￿rectory);

.3/

/\ Create the file TEST_FILE for writing, if it does not exist￿. Give the owner authority to read, write, and execute. \/ FilDes = open(TEST_FILE, O_WRONLY O_CREAT O_EXCL, S_IRWXU); if ( -1 == FilDes )

{

perror("open Error"); CleanUpOnError(2); return ð;

}

printf("Created %s in directory %s.\n",TEST_FILE,InitialDir￿ectory);

.4/

/\ Write TEST_DATA to TEST_FILE via FilDes \/ BytesWritten = write(FilDes,TEST_DATA,strlen(TEST_DATA)); if ( -1 == BytesWritten )

{

perror("write Error"); CleanUpOnError(3); return ð;

}

printf("Wrote %s to file %s.\n",TEST_DATA,TEST_FILE);

.5/

/\ Close TEST_FILE via FilDes \/

if ( -1 == close(FilDes) )

{

perror("close Error"); CleanUpOnError(4); return ð;

}

FilDes = -1;

printf("File %s closed.\n",TEST_FILE);

.6/

/\ Open the TEST_FILE file for reading only. \/

if ( -1 == (FilDes = open(TEST_FILE,O_RDONLY)) )

{

Appendix B. Original Examples in Additional BLanguages-177