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diff --git a/man3p/atoi.3p b/man3p/atoi.3p new file mode 100644 index 000000000..78375b66a --- /dev/null +++ b/man3p/atoi.3p @@ -0,0 +1,87 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "ATOI" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" atoi +.SH NAME +atoi \- convert a string to an integer +.SH SYNOPSIS +.LP +\fB#include <stdlib.h> +.br +.sp +int atoi(const char *\fP\fIstr\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +The call \fIatoi\fP(\fIstr\fP) shall be equivalent to: +.sp +.RS +.nf + +\fB(int) strtol(str, (char **)NULL, 10) +\fP +.fi +.RE +.LP +except that the handling of errors may differ. If the value cannot +be represented, the behavior is undefined. +.SH RETURN VALUE +.LP +The \fIatoi\fP() function shall return the converted value if the +value can be represented. +.SH ERRORS +.LP +No errors are defined. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.SS Converting an Argument +.LP +The following example checks for proper usage of the program. If there +is an argument and the decimal conversion of this +argument (obtained using \fIatoi\fP()) is greater than 0, then the +program has a valid number of minutes to wait for an event. +.sp +.RS +.nf + +\fB#include <stdlib.h> +#include <stdio.h> +\&... +int minutes_to_event; +\&... +if (argc < 2 || ((minutes_to_event = atoi (argv[1]))) <= 0) { + fprintf(stderr, "Usage: %s minutes\\n", argv[0]); exit(1); +} +\&... +\fP +.fi +.RE +.SH APPLICATION USAGE +.LP +The \fIatoi\fP() function is subsumed by \fIstrtol\fP() but is retained +because it is +used extensively in existing code. If the number is not known to be +in range, \fIstrtol\fP() should be used because \fIatoi\fP() is not +required to perform any error +checking. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIstrtol\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001, +\fI<stdlib.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |