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Flag (programming)

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239: 296: 65:, and the meaning of the value contained in a flag will generally be defined in relation to the data structure it is part of. In many cases, the binary value of a flag will be understood to represent one of several possible states or statuses. In other cases, the binary values may represent one or more attributes in a 69:, often related to abilities or permissions, such as "can be written to" or "can be deleted". However, there are many other possible meanings that can be assigned to flag values. One common use of flags is to mark or designate data structures for future processing. 76:
and other logic devices, flags are commonly used to control or indicate the intermediate or final state or outcome of different operations. Microprocessors typically have, for example, a
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that is composed of such flags, and the flags are used to indicate various post-operation conditions, such as when there has been an
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that translates command line switches into flags in the sense of this article.
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will result in a jump if the Z (zero) flag was set by some previous operation.
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conditions, such as file empty or full queue statuses.
196: 348: 163: 331: 274: 206:Learning Ruby: The Language that Powers Rails 57:Flags may be found as members of a defined 338: 324: 281: 267: 202: 14: 349: 169: 290: 233: 107:programs often start with an option 92:(Jump if Equal) instruction in the 24: 25: 393: 294: 237: 176:. Elsevier Science. p. 59. 103:is also referred to as a flag. 209:. O'Reilly Media. p. 49. 13: 1: 156: 310:. You can help Knowledge by 253:. You can help Knowledge by 7: 362:Operating system technology 173:Designing Computer Programs 114: 10: 398: 289: 232: 136:FLAGS register (computing) 42:that are used to store a 38:can refer to one or more 367:Central processing unit 203:Fitzgerald, M. (2007). 146:Semaphore (programming) 382:Computer science stubs 377:Operating system stubs 249:-related article is a 50:for signaling special 27:Computer data variable 94:X86 assembly language 32:computer programming 141:Program status word 101:command line switch 82:arithmetic overflow 357:Programming idioms 170:Haigh, J. (1994). 372:Digital registers 319: 318: 262: 261: 216:978-0-596-55532-0 183:978-0-08-050403-2 86:jump instructions 16:(Redirected from 389: 340: 333: 326: 304:computer science 298: 291: 283: 276: 269: 247:operating-system 241: 234: 227: 226: 224: 223: 200: 194: 193: 191: 190: 167: 126:Control register 88:. For example a 48:Boolean variable 21: 18:Flag (computing) 397: 396: 392: 391: 390: 388: 387: 386: 347: 346: 345: 344: 288: 287: 231: 230: 221: 219: 217: 201: 197: 188: 186: 184: 168: 164: 159: 151:Status register 131:Enumerated type 117: 78:status register 74:microprocessors 63:database record 28: 23: 22: 15: 12: 11: 5: 395: 385: 384: 379: 374: 369: 364: 359: 343: 342: 335: 328: 320: 317: 316: 299: 286: 285: 278: 271: 263: 260: 259: 242: 229: 228: 215: 195: 182: 161: 160: 158: 155: 154: 153: 148: 143: 138: 133: 128: 123: 116: 113: 59:data structure 26: 9: 6: 4: 3: 2: 394: 383: 380: 378: 375: 373: 370: 368: 365: 363: 360: 358: 355: 354: 352: 341: 336: 334: 329: 327: 322: 321: 315: 313: 309: 306:article is a 305: 300: 297: 293: 292: 284: 279: 277: 272: 270: 265: 264: 258: 256: 252: 248: 243: 240: 236: 235: 218: 212: 208: 207: 199: 185: 179: 175: 174: 166: 162: 152: 149: 147: 144: 142: 139: 137: 134: 132: 129: 127: 124: 122: 119: 118: 112: 110: 106: 102: 97: 95: 91: 87: 83: 79: 75: 70: 68: 64: 60: 55: 53: 49: 45: 41: 37: 33: 19: 312:expanding it 301: 255:expanding it 244: 220:. Retrieved 205: 198: 187:. Retrieved 172: 165: 105:Command line 98: 89: 71: 61:, such as a 56: 35: 29: 46:value or a 351:Categories 222:2023-07-31 189:2023-07-31 157:References 121:Bit field 67:bit field 115:See also 72:Within 213:  180:  109:parser 44:binary 302:This 245:This 308:stub 251:stub 211:ISBN 178:ISBN 52:code 40:bits 36:flag 30:In 353:: 99:A 90:je 34:, 339:e 332:t 325:v 314:. 282:e 275:t 268:v 257:. 225:. 192:. 20:)

Index

Flag (computing)
computer programming
bits
binary
Boolean variable
code
data structure
database record
bit field
microprocessors
status register
arithmetic overflow
jump instructions
X86 assembly language
command line switch
Command line
parser
Bit field
Control register
Enumerated type
FLAGS register (computing)
Program status word
Semaphore (programming)
Status register
Designing Computer Programs
ISBN
978-0-08-050403-2
Learning Ruby: The Language that Powers Rails
ISBN
978-0-596-55532-0

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