4.1cBSD/usr/man/man3/intro.3
.TH INTRO 3 "25 February 1983"
.SH NAME
intro \- introduction to library functions
.SH DESCRIPTION
This section describes functions that may be found
in various libraries. The library functions are those other than the
functions which directly invoke UNIX system primitives, described in section 2.
This section has the libraries physically grouped together. This is a
departure from older versions of the UNIX Programmer's Reference Manual,
which did not group functions by library.
The functions described in this section are grouped into various libraries:
.TP 6n
(3) and (3S)
The straight ``(3)'' functions are the standard C library functions. The
C library also includes all the functions described in section 2. The
3S functions comprise the standard I/O library. Together with the (3N)
and (3X) routines, these functions
constitute library \fIlibc\fP,
which is automatically loaded by the C compiler
.IR cc (1)
and the Fortran compiler
.IR f77 (1).
The link editor
.IR ld (1)
searches this library under the `\-lc' option.
Declarations for some of these functions may be obtained
from include files indicated on the appropriate pages.
.TP
(3F)
The 3F functions are all functions callable from FORTRAN. These
functions perform the same jobs as do the straight ``(3)'' functions.
.TP
(3J)
These functions are part of the job control facilities,
contained in the library
.RB \*(lq \-ljobs .\*(rq
The job control facilities are outlined in
.IR intro (3J).
.TP
(3M)
These functions constitute the math library,
.I libm.
They are automatically loaded as needed by the Fortran compiler
.IR f77 (1).
The link editor searches this library under the \*(lq\-lm\*(rq option.
Declarations for these functions may be obtained from the include file
.RI < math.h >.
.TP
(3N)
These functions constitute the internet network library,
.TP
(3S)
These functions constitute the `standard I/O package', see
.IR stdio (3S).
These functions are in the library
.I libc
already mentioned. Declarations for these functions may be obtained from
the include file
.RI < stdio.h >.
.TP
(3X)
Various specialized libraries have not been given distinctive captions.
Files in which such libraries are found are named on appropriate pages.
.SH FILES
.nf
/lib/libc.a
/usr/lib/libm.a
/usr/lib/libjobs.a
.fi
.SH SEE ALSO
stdio(3),
nm(1), ld(1), cc(1), f77(1), intro(2)
.SH DIAGNOSTICS
Functions in the math library (3M) may return
conventional values when the function is undefined for the
given arguments or when the value is not representable.
In these cases the external variable
.I errno
(see
.IR intro (2))
is set to the value EDOM (domain error) or ERANGE (range error).
The values of EDOM and ERANGE are defined in the include file
.RI < math.h >.
. \".SH "ASSEMBLER (PDP-11)"
. \"In assembly language these functions may be accessed
. \"by simulating the C calling sequence.
. \"For example,
. \".IR ecvt (3)
. \"might be called this way:
. \".IP ""
. \".globl _ecvt
. \".nf
. \"setd
. \"mov $sign,\-(sp)
. \"mov $decpt,\-(sp)
. \"mov ndigit,\-(sp)
. \"movf value,\-(sp)
. \"jsr pc,_ecvt
. \"add $14.,sp
. \".fi
.SH "LIST OF FUNCTIONS"
The functions listed below are those available in the C library.
Function names which are indented below others appear on the same manual
page as the one from which they are indented. For example,
.I setkey
appears on the same manual page as does
.IR crypt ,
but it is
.I crypt
which actually appears at the head of the manual page.
.sp
.ta 0.3i 2.5i
.nf
abort exit and generate a core dump
abs integer absolute value
atof convert ASCII to numbers
atoi convert ASCII to numbers (see atof.3)
atol convert ASCII to numbers (see atof.3)
bstring byte string manipulation routines
bcopy copy a byte string
bcmp compare two byte strings
bzero zero a byte string
crypt DES encryption
setkey DES encryption (see crypt.3)
encrypt DES encryption (see crypt.3)
ctime convert date and time to ASCII
localtime convert date and time to ASCII (see ctime.3)
gmtime convert date and time to ASCII (see ctime.3)
asctime convert date and time to ASCII (see ctime.3)
timezone convert date and time to ASCII (see ctime.3)
ctype character classification
isalpha test character is alphabetic (see ctype.3)
isupper test character is upper case (see ctype.3)
islower test character is lower case (see ctype.3)
isdigit test character is digit (see ctype.3)
isalnum test character is letter or digit (see ctype.3)
isspace test character is whitespace (see ctype.3)
ispunct test character is punctuation (see ctype.3)
isprint test character is printable (see ctype.3)
iscntrl test character is a control character (see ctype.3)
isascii test character is ASCII (see ctype.3)
ecvt output conversion
fcvt output conversion (see ecvt.3)
gcvt output conversion (see ecvt.3)
end last locations in program
etext last locations in program (see end.3)
edata last locations in program (see end.3)
frexp split into mantissa and exponent
ldexp split into mantissa and exponent (see frexp.3)
modf split into mantissa and exponent (see frexp.3)
getenv value for environment name
getfsent file system descriptor file entry
getfsspec file system descriptor file entry (see getfsent.3)
getfsfile file system descriptor file entry (see getfsent.3)
setfsent file system descriptor file entry (see getfsent.3)
endfsent file system descriptor file entry (see getfsent.3)
getgrent group file entry
getgrgid group file entry (see getgrent.3)
getgrnam group file entry (see getgrent.3)
setgrent group file entry (see getgrent.3)
endgrent group file entry (see getgrent.3)
getlogin login name
getpass read a password
getpw get name from uid
getpwent password file entry
getpwuid password file entry (see getpwent.3)
getpwnam password file entry (see getpwent.3)
setpwent password file entry (see getpwent.3)
endpwent password file entry (see getpwent.3)
initgroups initialize group access list
intro introduction to library functions
malloc main memory allocator
free main memory allocator (see malloc.3)
realloc main memory allocator (see malloc.3)
calloc main memory allocator (see malloc.3)
mktemp make a unique file name
monitor prepare execution profile
monstartup prepare execution profile (see monitor.3)
nlist get entries from name list
perror system error messages
sys_errlist, sys_nerr system error messages (see perror.3)
sys_nerr system error messages (see perror.3)
psignal signal messages
sys_siglist signal messages (see psignal.3)
qsort quicker sort
rand random number generator
srand random number generator (see rand.3)
random better random number generator
srandom better random number generator (see random.3)
initstate routines for changing generators (see random.3)
setstate routines for changing generators (see random.3)
regex regular expression handler
re_comp regular expression compiler (see regex.3)
re_exec compiled regular expression interpreter (see regex.3)
scandir scan a directory
setjmp non-local goto
longjmp non-local goto (see setjmp.3)
sleep suspend execution for interval
string string operations
strcat concatenate null terminated strings (see string.3)
strncat concatenate n characters (see string.3)
strcmp compare strings (see string.3)
strncmp compare n characters (see string.3)
strcpy copy string (see string.3)
strncpy copy n characters (see string.3)
strlen obtain string length (see string.3)
index find first occurrence of character in string (see string.3)
rindex find last occurrence of character in string (see string.3)
swab swap bytes
system issue a shell command
ttyname find name of a terminal
valloc aligned memory allocator
varargs variable argument list
.fi