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This chapter summarizes whether or not it's safe to use the C Library functions:
 |
The functions designated as threadsafe are safe only if you create threads with _beginthread(), not tfork(). |
Use these links to find a function quickly:
| A | B | C | D | E | F | G | H | I | J | K | L |
| M | N | O | P | Q | R | S | T | U | V | W | Y |
Here's how to interpret the entries:
| If the entry is: | The function: |
|---|---|
| Yes | Is safe to use. |
| No | Isn't safe to use. |
| errno | Is safe to use, but may change the value of errno. |
| Depends | Might be safe to use - see the function's Caveats section for more information. |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| abort() | No | Yes | Yes |
| abs() | Yes | Yes | Yes |
| access(), _access() | No | errno | Yes |
| acos() | No | No | Yes |
| acosh() | No | No | Yes |
| alarm() | No | errno | Yes |
| alloca() | No | Yes | Yes |
| asctime(), _asctime() | No | No | Yes |
| asin() | No | No | Yes |
| asinh() | No | No | Yes |
| assert() | No | No | Yes |
| atan() | No | No | Yes |
| atan2() | No | No | Yes |
| atanh() | No | No | Yes |
| atexit() | No | No | Yes |
| atof() | No | No | Yes |
| atoh() | Yes | Yes | Yes |
| atoi() | Yes | Yes | Yes |
| atol() | Yes | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| basename() | Yes | Yes | Yes |
| _bcalloc() | No??? | No??? | Yes??? |
| _beginthread() | No | No | Yes |
| _bexpand() | No??? | No??? | Yes??? |
| _bfree() | No??? | No??? | Yes??? |
| _bfreeseg() | Unknown | Unknown | Unknown |
| _bgetcmd() | Yes | Yes | Yes |
| _bheapchk() | No??? | No??? | Yes??? |
| _bheapmin() | No??? | No??? | Yes??? |
| _bheapseg() | Unknown | Unknown | Unknown |
| _bheapset() | No??? | No??? | Yes??? |
| _bheapshrink() | No??? | No??? | Yes??? |
| _bheapwalk() | No??? | No??? | Yes??? |
| block_read() | No | errno | Yes |
| block_write() | No | errno | Yes |
| _bmalloc() | No??? | No??? | No??? |
| _bmsize() | Yes??? | Yes??? | Yes??? |
| _bprintf() | No | errno | Yes |
| _brealloc() | No??? | No??? | Yes??? |
| bsearch() | Yes | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| cabs() | No | No | Yes |
| calloc() | No | No | Yes |
| _CA_PCI_BIOS_Present() | No | No | No |
| _CA_PCI_Find_Class() | No | No | No |
| _CA_PCI_Find_Device() | No | No | No |
| _CA_PCI_Generate_SpecialCycle() | No | No | No |
| _CA_PCI_Read_Config_Byte() | No | No | No |
| _CA_PCI_Read_Config_DWord() | No | No | No |
| _CA_PCI_Read_Config_Word() | No | No | No |
| _CA_PCI_Write_Config_Byte() | No | No | No |
| _CA_PCI_Write_Config_DWord() | No | No | No |
| _CA_PCI_Write_Config_Word() | No | No | No |
| ceil() | No | No | Yes |
| cfgetispeed() | Yes | Yes | Yes |
| cfgetospeed() | Yes | Yes | Yes |
| cfsetispeed() | Yes | Yes | Yes |
| cfsetospeed() | Yes | Yes | Yes |
| cgets() | No | errno | Yes |
| chdir() | No | errno | Yes |
| chmod() | No | errno | Yes |
| chown() | No | errno | Yes |
| chsize() | No | errno | Yes |
| _clear87() | No | No | Yes |
| clearenv() | No | No | Yes |
| clearerr() | Yes | Yes | Yes |
| clock() | No | Yes | Yes |
| clock_getres() | No | errno | Yes |
| clock_gettime() | No | errno | Yes |
| clock_setres() | No | errno | Yes |
| clock_settime() | No | errno | Yes |
| close() | No | errno | Yes |
| closedir() | No | No | Yes |
| closelog() | No | No | Yes |
| _cmdname() | No | errno | Yes |
| confstr() | Yes | errno | Yes |
| console_active() | No | errno | Yes |
| console_arm() | No | errno | Yes |
| console_close() | No | No | Yes |
| console_ctrl() | No | errno | Yes |
| console_font() | No | errno | Yes |
| console_info() | No | errno | Yes |
| console_open() | No | No | Yes |
| console_protocol() | No | errno | Yes |
| console_read() | No | errno | Yes |
| console_size() | No | errno | Yes |
| console_state() | No | errno | Yes |
| console_write() | No | errno | Yes |
| _control87() | No | No | Yes |
| cos() | No | No | Yes |
| cosh() | No | No | Yes |
| cprintf() | No | errno | Yes |
| cputs() | No | errno | Yes |
| creat() | No | errno | Yes |
| Creceive() | No | errno | Yes |
| Creceivemx() | No | errno | Yes |
| cscanf() | No | errno | Yes |
| ctermid() | No | Depends | Depends |
| ctime() | No | No | No |
| _ctime() | No | errno | Yes |
| cuserid() | No | No | No |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| delay() | No | No | No |
| dev_arm() | No | errno | Yes |
| dev_fdinfo() | No | errno | Yes |
| dev_info() | No | errno | Yes |
| dev_insert_chars() | No | errno | Yes |
| dev_ischars() | No | errno | Yes |
| dev_mode() | No | errno | Yes |
| dev_osize() | No | errno | Yes |
| dev_read() | No | Depends | Depends |
| dev_readex() | No | errno | Yes |
| dev_size() | No | errno | Yes |
| dev_state() | No | errno | Yes |
| difftime() | No | No | Yes |
| _disable() | Yes | Yes | Yes |
| disk_get_entry() | No | errno | Yes |
| disk_space() | No | errno | Yes |
| div() | Yes | Yes | Yes |
| dup() | No | errno | Yes |
| dup2() | No | errno | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| ecvt(), _ecvt() | No | No | Yes |
| _enable() | Yes | Yes | Yes |
| endgrent() | No | No | No |
| endpwent() | No | No | No |
| _endthread() | No | No | Yes |
| eof() | No | errno | Yes |
| exec... functions | No | errno | Yes |
| _exit() | No | Yes | Yes |
| exit() | No | No | Yes |
| exp() | No | No | Yes |
| _expand() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| fabs() | No | No | Yes |
| _fcalloc() | No??? | No??? | Yes??? |
| fchmod() | No | errno | Yes |
| fchown() | No | errno | Yes |
| fclose() | No | No | Yes |
| fcloseall() | No | No | Yes |
| fcntl() | No | errno | Yes |
| fcvt(), _fcvt() | No | No | Yes |
| fdatasync() | No | errno | Yes |
| fdopen() | No | No | Yes |
| feof() | No | No | Yes |
| ferror() | No | No | Yes |
| _fexpand() | No??? | No??? | Yes??? |
| fflush() | No | No | Yes |
| _ffree() | No??? | No??? | Yes??? |
| fgetc() | No | No | Yes |
| fgetchar() | No | No | Yes |
| fgetpos() | No | No | Yes |
| fgets() | No | No | Yes |
| _fheapchk() | No??? | No??? | Yes??? |
| _fheapgrow() | No??? | No??? | Yes??? |
| _fheapmin() | No??? | No??? | Yes??? |
| _fheapset() | No??? | No??? | Yes??? |
| _fheapshrink() | No??? | No??? | Yes??? |
| _fheapwalk() | No??? | No??? | Yes??? |
| filelength() | No | No | Yes |
| fileno() | No | Yes | Yes |
| floor() | No | No | Yes |
| flushall() | No | No | Yes |
| _fmalloc() | No??? | No??? | No??? |
| _fmemccpy() | Yes | Yes | Yes |
| _fmemchr() | Yes | Yes | Yes |
| _fmemcmp() | Yes | Yes | Yes |
| _fmemcpy() | Yes | Yes | Yes |
| _fmemicmp() | Yes | Yes | Yes |
| _fmemmove() | Yes | Yes | Yes |
| _fmemset() | Yes | Yes | Yes |
| fmod() | No | No | Yes |
| _fmsize() | Yes??? | Yes??? | Yes??? |
| fnmatch() | Yes | Yes | Yes |
| fopen() | No | No | Yes |
| fork() | No | errno | Yes |
| fpathconf() | No | errno | Yes |
| FP_OFF() | Yes | Yes | Yes |
| _fpreset() | No | No | Yes |
| fprintf() | No | No | Yes |
| FP_SEG() | Yes | Yes | Yes |
| fputc() | No | No | Yes |
| fputchar() | No | No | Yes |
| fputs() | No | No | Yes |
| fread() | No | No | Yes |
| _frealloc() | No??? | No??? | Yes??? |
| free() | No | No | Yes |
| _freect() | No | No | Yes |
| freopen() | No | No | Yes |
| frexp() | No | No | Yes |
| fscanf() | No | No | Yes |
| fseek() | No | No | Yes |
| fsetpos() | No | No | Yes |
| _fsopen() | No | No | Yes |
| fstat() | No | errno | Yes |
| _fstrcat() | Yes | Yes | Yes |
| _fstrchr() | Yes | Yes | Yes |
| _fstrcmp() | Yes | Yes | Yes |
| _fstrcpy() | Yes | Yes | Yes |
| _fstrcspn() | Yes | Yes | Yes |
| _fstrdup() | No | No | Yes |
| _fstricmp() | Yes | Yes | Yes |
| _fstrlen() | Yes | Yes | Yes |
| _fstrlwr() | Yes | Yes | Yes |
| _fstrncat() | Yes | Yes | Yes |
| _fstrncmp() | Yes | Yes | Yes |
| _fstrncpy() | Yes | Yes | Yes |
| _fstrnicmp() | Yes | Yes | Yes |
| _fstrnset() | Yes | Yes | Yes |
| _fstrpbrk() | Yes | Yes | Yes |
| _fstrrchr() | Yes | Yes | Yes |
| _fstrrev() | Yes | Yes | Yes |
| _fstrset() | Yes | Yes | Yes |
| _fstrspn() | Yes | Yes | Yes |
| _fstrstr() | Yes | Yes | Yes |
| _fstrtok() | No | No | No |
| _fstrupr() | Yes | Yes | Yes |
| fsync() | No | errno | Yes |
| fsys_fdinfo() | No | errno | Yes |
| fsys_fstat() | No | errno | Yes |
| fsys_get_mount_dev() | No | errno | Yes |
| fsys_get_mount_pt() | No | errno | Yes |
| fsysinfo() | No | errno | Yes |
| fsys_stat() | No | errno | Yes |
| ftell() | No | No | Yes |
| ftime() | No | errno | Yes |
| _fullpath() | Yes | Yes | Yes |
| fwrite() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| gcvt(), _gcvt() | No | No | Yes |
| getc() | No | No | Yes |
| getch() | No | Yes | Yes |
| getchar() | No | No | Yes |
| getche() | No | Yes | Yes |
| getcmd() | No | errno | Yes |
| getcwd() | No | No | Yes |
| getegid() | No | Yes | Yes |
| getenv() | No | No | No |
| geteuid() | No | Yes | Yes |
| getgid() | No | Yes | Yes |
| getgrent() | No | No | No |
| getgrgid() | No | No | No |
| getgrnam() | No | No | No |
| getgroups() | No | errno | Yes |
| getlogin() | No | No | No |
| getnid() | No | Yes | Yes |
| getopt() | No | No | No |
| getpgrp() | No | Yes | Yes |
| getpid() | No | Yes | Yes |
| getppid() | No | Yes | Yes |
| getprio() | No | errno | Yes |
| getpwent() | No | No | No |
| getpwnam() | No | No | No |
| getpwuid() | No | No | No |
| gets() | No | No | Yes |
| getsid() | No | No | No |
| getuid() | No | Yes | No |
| gmtime(), _gmtime() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| halloc() | Unknown | Unknown | Unknown |
| _heapchk() | No | No | Yes |
| _heapenable() | No | No | Yes |
| _heapgrow() | No | No | Yes |
| _heapmin() | No | No | Yes |
| _heapset() | No | No | Yes |
| _heapshrink() | No | No | Yes |
| _heapwalk() | No | No | Yes |
| hfree() | Unknown | Unknown | Unknown |
| hypot() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| inp() | Yes | Yes | Yes |
| inpd() | Yes | Yes | Yes |
| input_line() | No | No | No |
| inpw() | Yes | Yes | Yes |
| ioctl() | No | No | No |
| isalnum() | Yes | Yes | Yes |
| isalpha() | Yes | Yes | Yes |
| isascii(), __isascii() | Yes | Yes | Yes |
| isatty() | No | No | No |
| iscntrl() | Yes | Yes | Yes |
| __iscsym() | Yes | Yes | Yes |
| __iscsymf() | Yes | Yes | Yes |
| isdigit() | Yes | Yes | Yes |
| isgraph() | Yes | Yes | Yes |
| islower() | Yes | Yes | Yes |
| isprint() | Yes | Yes | Yes |
| ispunct() | Yes | Yes | Yes |
| isspace() | Yes | Yes | Yes |
| isupper() | Yes | Yes | Yes |
| isxdigit() | Yes | Yes | Yes |
| itoa(), _itoa() | No | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| j0() | No | No | Yes |
| j1() | No | No | Yes |
| jn() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| kbhit() | No | No | Yes |
| kill() | No | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| labs() | No | Yes | Yes |
| ldexp() | No | No | Yes |
| ldiv() | No | Yes | Yes |
| lfind() | No | Yes | Yes |
| link() | No | Yes | No |
| localeconv() | No | No | Yes |
| localtime(), _localtime() | No | No | Yes |
| lock() | No | No | Yes |
| locking(), _locking() | No | No | Yes |
| log() | No | No | Yes |
| log10() | No | No | Yes |
| log2() | No | No | Yes |
| longjmp() | No | Yes | Yes |
| _lrotl() | Yes | Yes | Yes |
| _lrotr() | Yes | Yes | Yes |
| lsearch() | No | No | Yes |
| lseek() | No | Yes | No |
| lstat() | No | No | No |
| ltoa(), _ltoa() | No | Yes | Yes |
| ltrunc() | No | No | No |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| _makepath() | Yes | Yes | Yes |
| malloc() | No | No | No |
| matherr() | No | No | No |
| max(), __max() | Yes | Yes | Yes |
| mblen() | Yes | Yes | Yes |
| mbstowcs() | Yes | Yes | Yes |
| mbtowc() | Yes | Yes | Yes |
| _memavl() | No | No | No |
| memccpy() | Yes | Yes | Yes |
| memchr() | Yes | Yes | Yes |
| memcmp() | Yes | Yes | Yes |
| memcpy() | Yes | Yes | Yes |
| memicmp(), _memicmp() | Yes | Yes | Yes |
| _memmax() | No | No | Yes |
| memmove() | Yes | Yes | Yes |
| memset() | Yes | Yes | Yes |
| min(), __min() | Yes | Yes | Yes |
| mkdir() | No | Yes | Yes |
| mkfifo() | No | Yes | Yes |
| MK_FP() | Yes | Yes | Yes |
| mknod() | No | Yes | Yes |
| mktime() | No | Yes | Yes |
| mmap() | No | Yes | Yes |
| modf() | No | No | Yes |
| mount() | No | Yes | Yes |
| mouse_close() | No | No | Yes |
| mouse_flush() | No | No | Yes |
| mouse_open() | No | No | Yes |
| mouse_param() | No | No | Yes |
| mouse_read() | No | No | Yes |
| movedata() | Yes | Yes | Yes |
| mprotect() | No | Yes | Yes |
| mq_close() | No | errno | Yes |
| mq_getattr() | No | errno | Yes |
| mq_notify() | No | errno | Yes |
| mq_open() | No | errno | No |
| mq_receive() | No | errno | Yes |
| mq_send() | No | errno | Yes |
| mq_setattr() | No | errno | Yes |
| mq_unlink() | No | errno | No |
| _msize() | Yes | Yes | Yes |
| munmap() | No | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| nanosleep() | No | No | No |
| _ncalloc() | No | No | Yes |
| _nexpand() | No | No | Yes |
| _nfree() | No | No | Yes |
| _nheapchk() | No | No | Yes |
| _nheapgrow() | No | No | Yes |
| _nheapmin() | No | No | Yes |
| _nheapset() | No | No | Yes |
| _nheapshrink() | No | No | Yes |
| _nheapwalk() | No | No | Yes |
| _nmalloc() | No | No | No |
| _nmsize() | Yes | Yes | Yes |
| nosound() | Yes | Yes | Yes |
| _nrealloc() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| offsetof() | Yes | Yes | Yes |
| onexit() | No | No | Yes |
| open() | No | Yes | Yes |
| opendir() | No | No | Yes |
| openlog() | No | No | Yes |
| outp() | Yes | Yes | Yes |
| outpd() | Yes | Yes | Yes |
| outpw() | Yes | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| pathconf() | No | Yes | Yes |
| pause() | No | Yes | Yes |
| pclose() | No | No | No |
| perror() | No | No | Yes |
| pipe() | No | Yes | Yes |
| popen() | No | No | No |
| pow() | No | No | Yes |
| printf() | No | No | Yes |
| print_usage() | No | No | Yes |
| putc() | No | No | Yes |
| putch() | No | No | Yes |
| putchar() | No | No | Yes |
| putenv() | No | No | Yes |
| puts() | No | No | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| raise() | No | Yes | Yes |
| rand() | Yes | Yes | Yes |
| read() | No | errno | Yes |
| readdir() | No | No | Yes |
| readlink() | No | No | Yes |
| Readmsg() | No | errno | Yes |
| Readmsgmx() | No | errno | Yes |
| readv() | No | errno | Yes |
| realloc() | No | No | Yes |
| Receive() | No | errno | Yes |
| Receivemx() | No | errno | Yes |
| regcomp() | No | No | No |
| regerror() | Yes | Yes | Yes |
| regexec() | No | No | No |
| regfree() | No | No | Yes |
| Relay() | No | errno | Yes |
| remove() | No | No | Yes |
| rename() | No | No | Yes |
| Reply() | No | errno | Yes |
| Replymx() | No | errno | Yes |
| rewind() | No | No | Yes |
| rewinddir() | No | Yes | No |
| rmdir() | No | No | Yes |
| _rotl() | Yes | Yes | Yes |
| _rotr() | Yes | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| sbrk() | No | No | Yes |
| scanf() | No | No | Yes |
| sched_getparam() | No | errno | Yes |
| sched_getscheduler() | No | errno | Yes |
| sched_setparam() | No | errno | Yes |
| sched_setscheduler() | No | errno | Yes |
| sched_yield() | No | Yes | Yes |
| _searchenv() | No | No | Yes |
| searchenv() | No | No | Yes |
| segread() | No | Yes | Yes |
| select() | No | No | No |
| sem_destroy() | No | errno | Yes |
| sem_init() | No | errno | Depends |
| sem_post() | No | errno | Yes |
| sem_trywait() | No | errno | Yes |
| sem_wait() | No | errno | Yes |
| Send() | No | errno | Yes |
| Sendfd() | No | errno | Yes |
| Sendfdmx() | No | errno | Yes |
| Sendmx() | No | errno | Yes |
| setbuf() | No | No | Yes |
| setegid() | No | errno | Yes |
| setenv() | No | No | No |
| seteuid() | No | errno | Yes |
| setgid() | No | errno | Yes |
| setgrent() | No | No | No |
| setjmp() | No | Yes | Yes |
| setlocale() | No | No | No |
| setlogmask() | No | No | No |
| setmode() | No | No | Yes |
| _setmx() | Yes | Yes | Yes |
| set_new_handler(), _set_new_handler() | No | No | Yes |
| setpgid() | No | errno | Yes |
| setprio() | No | errno | Yes |
| setpwent() | No | No | No |
| setsid() | No | errno | Yes |
| setuid() | No | errno | Yes |
| setvbuf() | No | No | Yes |
| shm_open() | No | errno | Yes |
| shm_unlink() | No | errno | Yes |
| sigaction() | No | errno | Yes |
| sigaddset() | Yes | errno | Yes |
| sigdelset() | Yes | errno | Yes |
| sigemptyset() | Yes | errno | Yes |
| sigfillset() | Yes | errno | Yes |
| sigismember() | Yes | errno | Yes |
| siglongjmp() | No | Yes | Yes |
| signal() | No | errno | Yes |
| sigpending() | No | errno | Yes |
| sigprocmask() | No | errno | Yes |
| sigsetjmp() | No | Yes | Yes |
| sigsuspend() | No | errno | Yes |
| sin() | No | No | Yes |
| sinh() | No | No | Yes |
| sleep() | No | No | No |
| sopen() | No | No | Yes |
| sound() | Yes | Yes | Yes |
| spawn... functions | No | No | Yes |
| _splitpath() | No | Yes | Yes |
| _splitpath2() | No | Yes | Yes |
| sprintf() | No | No | Yes |
| sqrt() | No | No | Yes |
| srand() | Yes | Yes | Yes |
| sscanf() | No | No | Yes |
| stackavail() | No | Yes | Yes |
| stat() | No | No | Yes |
| _status87() | No | No | Yes |
| strcat() | Yes | Yes | Yes |
| strchr() | Yes | Yes | Yes |
| strcmp() | Yes | Yes | Yes |
| strcmpi() | Yes | Yes | Yes |
| strcoll() | Yes | Yes | Yes |
| strcpy() | Yes | Yes | Yes |
| strcspn() | Yes | Yes | Yes |
| _strdate() | No | Yes | Yes |
| strdup(), _strdup() | No | No | Yes |
| strerror() | No | Yes | Yes |
| strftime() | No | errno | Yes |
| stricmp(), _stricmp() | Yes | Yes | Yes |
| strlen() | Yes | Yes | Yes |
| strlwr(), _strlwr() | Yes | Yes | Yes |
| strncat() | Yes | Yes | Yes |
| strncmp() | Yes | Yes | Yes |
| strncpy() | Yes | Yes | Yes |
| strnicmp(), _strnicmp() | Yes | Yes | Yes |
| strnset() | Yes | Yes | Yes |
| strpbrk() | Yes | Yes | Yes |
| strrchr() | Yes | Yes | Yes |
| strrev(), _strrev() | Yes | Yes | Yes |
| strset(), _strset() | Yes | Yes | Yes |
| strspn() | Yes | Yes | Yes |
| strstr() | Yes | Yes | Yes |
| _strtime() | No | Yes | Yes |
| strtod() | No | errno | Yes |
| strtok() | No | No | No |
| strtol() | No | errno | Yes |
| strtoul() | No | errno | Yes |
| strupr(), _strupr() | Yes | Yes | Yes |
| strxfrm() | No | Yes | Yes |
| swab() | Yes | Yes | Yes |
| symlink() | No | errno | Yes |
| sync() | No | Yes | Yes |
| sysconf() | No | Yes | Yes |
| syslog() | No | No | No |
| system() | No | No | No |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| tan() | No | No | Yes |
| tanh() | No | No | Yes |
| tcdrain() | No | Yes | Yes |
| tcdropline() | No | Yes | Yes |
| tcflow() | No | Yes | Yes |
| tcflush() | No | Yes | Yes |
| tcgetattr() | No | Yes | Yes |
| tcgetpgrp() | No | Yes | Yes |
| tcsendbreak() | No | Yes | Yes |
| tcsetattr() | No | Yes | Yes |
| tcsetct() | No | Yes | Yes |
| tcsetpgrp() | No | Yes | Yes |
| tell() | No | Yes | Yes |
| tfork() | No | Yes | Yes |
| time() | No | Yes | Yes |
| timer_create() | No | Yes | Yes |
| timer_delete() | No | Yes | Yes |
| timer_gettime() | No | Yes | Yes |
| timer_settime() | No | Yes | Yes |
| times() | No | Yes | Yes |
| tmpfile() | No | No | No |
| tmpnam() | No | No | Yes |
| tolower(), _tolower() | Yes | Yes | Yes |
| toupper(), _toupper() | Yes | Yes | Yes |
| Trace... functions | Yes | Yes | Yes |
| Trigger() | No | Yes | Yes |
| ttyname() | No | No | No |
| tzset() | No | No | No |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| ultoa(), _ultoa() | No | Yes | Yes |
| umask() | No | Yes | Yes |
| umount() | No | No | No |
| uname() | No | Yes | Yes |
| ungetc() | No | No | Yes |
| ungetch() | No | No | Yes |
| unlink() | No | Yes | Yes |
| unlock() | No | Yes | Yes |
| utime() | No | Yes | Yes |
| utoa() | No | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| va_arg() | No | Yes | Yes |
| va_end() | No | Yes | Yes |
| va_start() | No | Yes | Yes |
| _vbprintf() | No | No | Yes |
| vcprintf() | No | Yes | Yes |
| vcscanf() | No | Yes | Yes |
| vfprintf() | No | Yes | Yes |
| vfscanf() | No | Yes | Yes |
| vprintf() | No | Yes | Yes |
| vscanf() | No | Yes | Yes |
| vsprintf() | No | Yes | Yes |
| vsscanf() | No | Yes | Yes |
| vsyslog() | No | No | No |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| wait() | No | Yes | Yes |
| waitpid() | No | Yes | Yes |
| wcstombs() | No | Yes | Yes |
| wctomb() | No | Yes | Yes |
| write() | No | Yes | Yes |
| Writemsg() | No | Yes | Yes |
| Writemsgmx() | No | Yes | Yes |
| writev() | No | Yes | Yes |
| Function | Int Hdlr | Sig Hdlr | Thread |
|---|---|---|---|
| y0() | No | No | Yes |
| y1() | No | No | Yes |
| Yield() | No | Yes | Yes |
| yn() | No | No | Yes |
|
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