Advanced Programming in the UNIX® Environment

ptg10805159

Appendix A Function Prototypes 867

int pclose(FILE *fp);

<stdio.h> p. 541

Returns: termination status ofpopencmdstring,−1 on error

void perror(const char *msg);

<stdio.h> p. 15

int pipe(intfd[2]);

<unistd.h> p. 535

Returns: 0 if OK,−1 on error

int poll(struct pollfdfdarray[], nfds_tnfds,inttimeout);

<poll.h> p. 506

Returns: count of ready descriptors, 0 on timeout,−1 on error

FILE *popen(const char *cmdstring,const char *type);

<stdio.h> p. 541

type:"r", "w"

Returns: file pointer if OK,NULLon error

int posix_openpt(intoflag);

<stdlib.h> p. 722

<fcntl.h>

oflag:O_RWDR, O_NOCTTY

Returns: file descriptor of next available PTY master if OK,

−1 on error

ssize_t pread(intfd,void *buf,size_tnbytes,off_toffset);

<unistd.h> p. 78

Returns: number of bytes read, 0 if end of file,−1 on error

int printf(const char *restrictformat,...);

<stdio.h> p. 159

Returns: number of characters output if OK, negative value

if output error

int pselect(intmaxfdp1,fd_set *restrictreadfds,

fd_set *restrictwritefds,fd_set *restrictexceptfds,

const struct timespec *restricttsptr,

const sigset_t *restrictsigmask);

<sys/select.h> p. 506

Returns: count of ready descriptors, 0 on timeout,−1 on error

void psiginfo(const siginfo_t *info,const char *msg);

<signal.h> p. 379