Math Processor Unit Library

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+.TH iatoi 3  "December 27, 2024" "libmpu" "LibMPU Programmer's Manual"
+.SH NAME
+\fBiatoi\fP, \fBiatoui\fP \- functions for converting ASCII string to integer number
+.SH SYNOPSIS
+.nf
+.B #include <libmpu.h>
+.PP
+.BI "void iatoi( mpu_int *" c ", __mpu_char8_t *" str ", int " nb " );
+.BI "void iatoui( mpu_int *" c ", __mpu_char8_t *" str ", int " nb " );
+.fi
+.SH DESCRIPTION
+The \fBiatoi()\fP, \fBiatoui()\fP functions are used to convert an ASCII string into numeric form.
+In the case of \fBiatoi()\fP function, the \fBstr\fP argument is considered as a pointer to a character
+array containing characters of a signed integer; in the case of \fBiatoui()\fP function, it is assumed
+that the string contains a representation of an unsigned integer type numeric constant.
+.PP
+Numeric constants in a string can be represented as binary, octal, hexadecimal, and decimal numbers.
+Binary numbers begin with the prefix \fB0b\fP or \fB0B\fP, for example, \fB0b1011\fP. The octal numbers
+must begin with '0' and contain digits from '0' through '7'. Hexadecimal constants begin with the prefix
+\fB0x\fP or \fB0X\fP and can contain characters from '0' to '7' and characters from 'a' to 'f' in any case.
+Decimal constants can contain characters from '0' to '9' but must not start with '0'. Before a number
+signs '+', '-' are allowed. If a string contains a binary, octal or hexadecimal constant, the sign
+is ignored.
+.PP
+The result is placed at \fBc\fP, and the parameter \fBnb\fP represents the size of the result \fBc\fP
+in bytes.
+.PP
+If the number represented in the \fBstr\fP string does not fit into the specified (\fBnb\fP) format, the
+overflow flag (\fBO\fP) is set.
+.PP
+The function affects the flags \fBA\fP, \fBC\fP, \fBO\fP, \fBP\fP, \fBS\fP, \fBZ\fP. Flags \fBA\fP, \fBC\fP
+flags are reset to 0. The flag \fBR\fP is not changed.
+.sp
+.SH EXAMPLES
+.nf
+.sp
+#include <libmpu.h>
+#include <stdio.h>
+
+int main( void )
+{
+  int  rc = 0;
+
+  __mpu_init();
+  __mpu_extra_warnings = 1;
+
+  {
+    mpu_int16_t    a, b;
+    int            nb = NB_I16;
+    __mpu_char8_t  s[32];
+
+    iatoui( a, "0b11", nb ); /* evaluate the A variable */
+    iatoi( b,  "-3", nb );   /* evaluate the B variable */
+
+    iitoa( s, a, RADIX_DEC, LOWERCASE, nb ); /* convert A value to ASCII string S */
+    printf( "a = %s;\\n", s ); /* a = 3; */
+
+    iitoa( s, b, RADIX_BIN, LOWERCASE, nb ); /* convert B value to ASCII string S */
+    printf( "b = %s;\\n", s ); /* b = 0b1111111111111101; */
+  }
+
+  __mpu_free_context();
+
+  return( rc );
+}
+.fi
+.SH SEE ALSO
+.BR iadd(3),
+.BR isub(3),
+.BR iadc(3),
+.BR isbb(3),
+.BR ishl(3),
+.BR ishr(3),
+.BR isal(3),
+.BR isar(3),
+.BR irol(3),
+.BR iror(3),
+.BR ircl(3),
+.BR ircr(3),
+.BR ishln(3),
+.BR ishrn(3),
+.BR isaln(3),
+.BR isarn(3),
+.BR iroln(3),
+.BR irorn(3),
+.BR ircln(3),
+.BR ircrn(3),
+.BR ineg(3),
+.BR inot(3),
+.BR iand(3),
+.BR itest(3),
+.BR icmp(3),
+.BR ior(3),
+.BR ixor(3),
+.BR iinc(3),
+.BR idec(3),
+.BR ixchg(3),
+.BR icpy(3),
+.BR icvt(3),
+.BR imul(3),
+.BR ismul(3),
+.BR idiv(3),
+.BR isdiv(3),
+.BR iitoa(3),
+.BR iuitoa(3).